• 337 questions

Periodic Table Worksheet

Read an element box, count protons, neutrons and electrons, and find elements by group and period, on screen or on paper, with the working after every answer.

Pick a sheet, then press Print the worksheet. To save a PDF, choose "Save as PDF" in the print window.

See all 337 with answers
Carbon is in group 14. How many valence electrons does a carbon atom have?

Pick an answer, then press Check answer. Then you see Correct or Not quite, with the reason. Keys: A to D pick, Enter checks.

Exam mode: 20 questions, 15 minutes.

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Unofficial practice questions, not affiliated with any school, textbook publisher or worksheet maker. Bank checked September 19, 2026.

Write-in worksheet: protons, neutrons and electrons 20 lines, made to print

Periodic table worksheet: protons, neutrons and electrons

Name ______________________ Date ____________

Use the reference table. For Part A, round the atomic mass to a whole number to get the mass number, then work out the rest.

Part A: fill in the row

  • Helium (He) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Carbon (C) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Oxygen (O) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Fluorine (F) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Sodium (Na) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Magnesium (Mg) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Aluminum (Al) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Phosphorus (P) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Chlorine (Cl) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Potassium (K) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Calcium (Ca) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____
  • Iron (Fe) Atomic number ____ Mass number ____ Protons ____ Neutrons ____ Electrons ____

Part B: work backward

  • An atom has 3 protons and 4 neutrons. Element ____________ Mass number ____ Electrons if neutral ____
  • An atom has 7 protons and 7 neutrons. Element ____________ Mass number ____ Electrons if neutral ____
  • An atom has 14 protons and 14 neutrons. Element ____________ Mass number ____ Electrons if neutral ____
  • An atom has 16 protons and 16 neutrons. Element ____________ Mass number ____ Electrons if neutral ____
  • An atom has 18 protons and 22 neutrons. Element ____________ Mass number ____ Electrons if neutral ____
  • An atom has 25 protons and 30 neutrons. Element ____________ Mass number ____ Electrons if neutral ____

Part C: explain in a sentence

  • Which number in an element box never changes from one atom of the element to the next, and why?
  • Chlorine has an atomic mass of 35.45. Explain why it is not a whole number.

Source: IUPAC Periodic Table of the Elements (4 May 2022), https://iupac.org/what-we-do/periodic-table-of-elements/; IUPAC CIAAW Abridged Standard Atomic Weights 2024, https://ciaaw.org/abridged-atomic-weights.htm; and the PubChem periodic table, https://pubchem.ncbi.nlm.nih.gov/periodic-table/. All read on 2026-09-19. Checked September 19, 2026.

Write-in worksheet: scavenger hunt, 18 clues made to print

Periodic table scavenger hunt

Name ______________________ Date ____________

You need a full periodic table that shows groups 1 to 18, the families and the state of each element. Write the element each clue leads to.

Find the element

  • 1. The noble gas in period 3 Name ____________ Symbol ____ Atomic number ____
  • 2. The halogen in period 4 Name ____________ Symbol ____ Atomic number ____
  • 3. The alkali metal in period 4 Name ____________ Symbol ____ Atomic number ____
  • 4. The alkaline earth metal in period 2 Name ____________ Symbol ____ Atomic number ____
  • 5. The only nonmetal in group 1 Name ____________ Symbol ____ Atomic number ____
  • 6. The element with twice as many protons as oxygen Name ____________ Symbol ____ Atomic number ____
  • 7. The first metal you reach counting up from atomic number 1 Name ____________ Symbol ____ Atomic number ____
  • 8. The only metalloid in period 3 Name ____________ Symbol ____ Atomic number ____
  • 9. The element in the same group as carbon and the same period as calcium Name ____________ Symbol ____ Atomic number ____
  • 10. The element directly above gold Name ____________ Symbol ____ Atomic number ____
  • 11. The period 4 element in group 8 Name ____________ Symbol ____ Atomic number ____
  • 12. The element whose atomic number equals the number of groups on the table Name ____________ Symbol ____ Atomic number ____
  • 13. The halogen with the fewest protons Name ____________ Symbol ____ Atomic number ____
  • 14. The element at the bottom of group 2 Name ____________ Symbol ____ Atomic number ____
  • 15. The element in the very last box of the table Name ____________ Symbol ____ Atomic number ____
  • 16. The noble gas with only 2 valence electrons Name ____________ Symbol ____ Atomic number ____
  • 17. The two elements that are liquids at room temperature ____________ and ____________
  • 18. The two metalloids of period 4 ____________ and ____________

Source: IUPAC Periodic Table of the Elements (4 May 2022), https://iupac.org/what-we-do/periodic-table-of-elements/; IUPAC CIAAW Abridged Standard Atomic Weights 2024, https://ciaaw.org/abridged-atomic-weights.htm; and the PubChem periodic table, https://pubchem.ncbi.nlm.nih.gov/periodic-table/. All read on 2026-09-19. Checked September 19, 2026.

Reference table: elements 1 to 36 made to print

Reference table: elements 1 to 36

Each line gives the atomic number, symbol and name, then the atomic mass, the group and period, and the family. Hand it out with either write-in worksheet.

Period 1

  • 1 H Hydrogen atomic mass 1.0080; group 1, period 1; nonmetal
  • 2 He Helium atomic mass 4.0026; group 18, period 1; noble gas

Period 2

  • 3 Li Lithium atomic mass 6.94; group 1, period 2; alkali metal
  • 4 Be Beryllium atomic mass 9.0122; group 2, period 2; alkaline earth metal
  • 5 B Boron atomic mass 10.81; group 13, period 2; metalloid
  • 6 C Carbon atomic mass 12.011; group 14, period 2; nonmetal
  • 7 N Nitrogen atomic mass 14.007; group 15, period 2; nonmetal
  • 8 O Oxygen atomic mass 15.999; group 16, period 2; nonmetal
  • 9 F Fluorine atomic mass 18.998; group 17, period 2; halogen
  • 10 Ne Neon atomic mass 20.180; group 18, period 2; noble gas

Period 3

  • 11 Na Sodium atomic mass 22.990; group 1, period 3; alkali metal
  • 12 Mg Magnesium atomic mass 24.305; group 2, period 3; alkaline earth metal
  • 13 Al Aluminum atomic mass 26.982; group 13, period 3; post-transition metal
  • 14 Si Silicon atomic mass 28.085; group 14, period 3; metalloid
  • 15 P Phosphorus atomic mass 30.974; group 15, period 3; nonmetal
  • 16 S Sulfur atomic mass 32.06; group 16, period 3; nonmetal
  • 17 Cl Chlorine atomic mass 35.45; group 17, period 3; halogen
  • 18 Ar Argon atomic mass 39.95; group 18, period 3; noble gas

Period 4

  • 19 K Potassium atomic mass 39.098; group 1, period 4; alkali metal
  • 20 Ca Calcium atomic mass 40.078; group 2, period 4; alkaline earth metal
  • 21 Sc Scandium atomic mass 44.956; group 3, period 4; transition metal
  • 22 Ti Titanium atomic mass 47.867; group 4, period 4; transition metal
  • 23 V Vanadium atomic mass 50.942; group 5, period 4; transition metal
  • 24 Cr Chromium atomic mass 51.996; group 6, period 4; transition metal
  • 25 Mn Manganese atomic mass 54.938; group 7, period 4; transition metal
  • 26 Fe Iron atomic mass 55.845; group 8, period 4; transition metal
  • 27 Co Cobalt atomic mass 58.933; group 9, period 4; transition metal
  • 28 Ni Nickel atomic mass 58.693; group 10, period 4; transition metal
  • 29 Cu Copper atomic mass 63.546; group 11, period 4; transition metal
  • 30 Zn Zinc atomic mass 65.38; group 12, period 4; transition metal
  • 31 Ga Gallium atomic mass 69.723; group 13, period 4; post-transition metal
  • 32 Ge Germanium atomic mass 72.630; group 14, period 4; metalloid
  • 33 As Arsenic atomic mass 74.922; group 15, period 4; metalloid
  • 34 Se Selenium atomic mass 78.971; group 16, period 4; nonmetal
  • 35 Br Bromine atomic mass 79.904; group 17, period 4; halogen
  • 36 Kr Krypton atomic mass 83.798; group 18, period 4; noble gas

Source: IUPAC Periodic Table of the Elements (4 May 2022), https://iupac.org/what-we-do/periodic-table-of-elements/; IUPAC CIAAW Abridged Standard Atomic Weights 2024, https://ciaaw.org/abridged-atomic-weights.htm; and the PubChem periodic table, https://pubchem.ncbi.nlm.nih.gov/periodic-table/. All read on 2026-09-19. Checked September 19, 2026.

Answer key for both write-in worksheets 38 lines, made to print

Answer key: write-in worksheets

Mass numbers in Part A come from rounding the atomic mass, the usual classroom rule. Part B uses the most common natural isotope of each element.

Protons, neutrons and electrons, Part A

  • Helium (He) atomic number 2, mass number 4 (from 4.0026), protons 2, neutrons 2, electrons 2
  • Carbon (C) atomic number 6, mass number 12 (from 12.011), protons 6, neutrons 6, electrons 6
  • Oxygen (O) atomic number 8, mass number 16 (from 15.999), protons 8, neutrons 8, electrons 8
  • Fluorine (F) atomic number 9, mass number 19 (from 18.998), protons 9, neutrons 10, electrons 9
  • Sodium (Na) atomic number 11, mass number 23 (from 22.990), protons 11, neutrons 12, electrons 11
  • Magnesium (Mg) atomic number 12, mass number 24 (from 24.305), protons 12, neutrons 12, electrons 12
  • Aluminum (Al) atomic number 13, mass number 27 (from 26.982), protons 13, neutrons 14, electrons 13
  • Phosphorus (P) atomic number 15, mass number 31 (from 30.974), protons 15, neutrons 16, electrons 15
  • Chlorine (Cl) atomic number 17, mass number 35 (from 35.45), protons 17, neutrons 18, electrons 17
  • Potassium (K) atomic number 19, mass number 39 (from 39.098), protons 19, neutrons 20, electrons 19
  • Calcium (Ca) atomic number 20, mass number 40 (from 40.078), protons 20, neutrons 20, electrons 20
  • Iron (Fe) atomic number 26, mass number 56 (from 55.845), protons 26, neutrons 30, electrons 26

Part B

  • 3 protons and 4 neutrons Lithium, mass number 7, 3 electrons
  • 7 protons and 7 neutrons Nitrogen, mass number 14, 7 electrons
  • 14 protons and 14 neutrons Silicon, mass number 28, 14 electrons
  • 16 protons and 16 neutrons Sulfur, mass number 32, 16 electrons
  • 18 protons and 22 neutrons Argon, mass number 40, 18 electrons
  • 25 protons and 30 neutrons Manganese, mass number 55, 25 electrons

Part C

  • The number that never changes The atomic number. It counts the protons, and the proton count is what makes an atom that element. Neutron counts differ between isotopes.
  • Why 35.45 is not a whole number It is a weighted average. Natural chlorine is about 76% chlorine-35 and about 24% chlorine-37.

Scavenger hunt

  • 1. The noble gas in period 3 Argon, Ar, atomic number 18
  • 2. The halogen in period 4 Bromine, Br, atomic number 35
  • 3. The alkali metal in period 4 Potassium, K, atomic number 19
  • 4. The alkaline earth metal in period 2 Beryllium, Be, atomic number 4
  • 5. The only nonmetal in group 1 Hydrogen, H, atomic number 1
  • 6. The element with twice as many protons as oxygen Sulfur, S, atomic number 16
  • 7. The first metal you reach counting up from atomic number 1 Lithium, Li, atomic number 3
  • 8. The only metalloid in period 3 Silicon, Si, atomic number 14
  • 9. The element in the same group as carbon and the same period as calcium Germanium, Ge, atomic number 32
  • 10. The element directly above gold Silver, Ag, atomic number 47
  • 11. The period 4 element in group 8 Iron, Fe, atomic number 26
  • 12. The element whose atomic number equals the number of groups on the table Argon, Ar, atomic number 18
  • 13. The halogen with the fewest protons Fluorine, F, atomic number 9
  • 14. The element at the bottom of group 2 Radium, Ra, atomic number 88
  • 15. The element in the very last box of the table Oganesson, Og, atomic number 118
  • 16. The noble gas with only 2 valence electrons Helium, He, atomic number 2
  • 17. Liquids at room temperature Bromine (Br, 35) and mercury (Hg, 80)
  • 18. Metalloids of period 4 Germanium (Ge, 32) and arsenic (As, 33)

Source: IUPAC Periodic Table of the Elements (4 May 2022), https://iupac.org/what-we-do/periodic-table-of-elements/; IUPAC CIAAW Abridged Standard Atomic Weights 2024, https://ciaaw.org/abridged-atomic-weights.htm; and the PubChem periodic table, https://pubchem.ncbi.nlm.nih.gov/periodic-table/. All read on 2026-09-19. Isotope abundances are from NIST Atomic Weights and Isotopic Compositions, read the same day. Checked September 19, 2026.

Next step Next: place all 118 elements on a blank table

All 337 questions with answers

Read an element box 42

  • An element box shows 3 at the top, then the symbol Li, the name Lithium, and 6.94 at the bottom. How many protons does one atom of this element have? Answer: 3. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 3 at the top, then the symbol Li, the name Lithium, and 6.94 at the bottom. What does the 3 tell you? Answer: Every lithium atom has 3 protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 3 at the top, then the symbol Li, the name Lithium, and 6.94 at the bottom. Which of these is the atomic number? Answer: 3. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • An element box shows 4 at the top, then the symbol Be, the name Beryllium, and 9.0122 at the bottom. How many electrons does a neutral atom of this element have? Answer: 4. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
Show all 337 questions (333 more)

Read an element box, continued

  • An element box shows 4 at the top, then the symbol Be, the name Beryllium, and 9.0122 at the bottom. What does the 9.0122 tell you? Answer: The average mass of beryllium atoms, in atomic mass units. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 4 at the top, then the symbol Be, the name Beryllium, and 9.0122 at the bottom. Which of these is the atomic number? Answer: 4. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • An element box shows 9 at the top, then the symbol F, the name Fluorine, and 18.998 at the bottom. How many electrons does a neutral atom of this element have? Answer: 9. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 9 at the top, then the symbol F, the name Fluorine, and 18.998 at the bottom. What does the 18.998 tell you? Answer: The average mass of fluorine atoms, in atomic mass units. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 9 at the top, then the symbol F, the name Fluorine, and 18.998 at the bottom. Which of these is the atomic mass? Answer: 18.998. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 11 at the top, then the symbol Na, the name Sodium, and 22.990 at the bottom. How many protons does one atom of this element have? Answer: 11. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 11 at the top, then the symbol Na, the name Sodium, and 22.990 at the bottom. Round the atomic mass to a whole number. What mass number do you get? Answer: 23. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 11 at the top, then the symbol Na, the name Sodium, and 22.990 at the bottom. What does the 11 tell you? Answer: Every sodium atom has 11 protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 19 at the top, then the symbol K, the name Potassium, and 39.098 at the bottom. How many electrons does a neutral atom of this element have? Answer: 19. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 19 at the top, then the symbol K, the name Potassium, and 39.098 at the bottom. What does the 39.098 tell you? Answer: The average mass of potassium atoms, in atomic mass units. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 19 at the top, then the symbol K, the name Potassium, and 39.098 at the bottom. Which of these is the atomic number? Answer: 19. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • An element box shows 26 at the top, then the symbol Fe, the name Iron, and 55.845 at the bottom. How many protons does one atom of this element have? Answer: 26. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 26 at the top, then the symbol Fe, the name Iron, and 55.845 at the bottom. Round the atomic mass to a whole number. What mass number do you get? Answer: 56. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 26 at the top, then the symbol Fe, the name Iron, and 55.845 at the bottom. Which of these is the atomic mass? Answer: 55.845. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 29 at the top, then the symbol Cu, the name Copper, and 63.546 at the bottom. How many electrons does a neutral atom of this element have? Answer: 29. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 29 at the top, then the symbol Cu, the name Copper, and 63.546 at the bottom. What does the 29 tell you? Answer: Every copper atom has 29 protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 29 at the top, then the symbol Cu, the name Copper, and 63.546 at the bottom. Which of these is the atomic number? Answer: 29. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • An element box shows 30 at the top, then the symbol Zn, the name Zinc, and 65.38 at the bottom. How many protons does one atom of this element have? Answer: 30. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 30 at the top, then the symbol Zn, the name Zinc, and 65.38 at the bottom. Round the atomic mass to a whole number. What mass number do you get? Answer: 65. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 30 at the top, then the symbol Zn, the name Zinc, and 65.38 at the bottom. Which of these is the atomic mass? Answer: 65.38. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 35 at the top, then the symbol Br, the name Bromine, and 79.904 at the bottom. Round the atomic mass to a whole number. What mass number do you get? Answer: 80. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 35 at the top, then the symbol Br, the name Bromine, and 79.904 at the bottom. What does the 79.904 tell you? Answer: The average mass of bromine atoms, in atomic mass units. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 35 at the top, then the symbol Br, the name Bromine, and 79.904 at the bottom. Which of these is the atomic mass? Answer: 79.904. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 47 at the top, then the symbol Ag, the name Silver, and 107.87 at the bottom. How many protons does one atom of this element have? Answer: 47. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 47 at the top, then the symbol Ag, the name Silver, and 107.87 at the bottom. What does the 47 tell you? Answer: Every silver atom has 47 protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 47 at the top, then the symbol Ag, the name Silver, and 107.87 at the bottom. Which of these is the atomic number? Answer: 47. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • An element box shows 50 at the top, then the symbol Sn, the name Tin, and 118.71 at the bottom. How many electrons does a neutral atom of this element have? Answer: 50. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 50 at the top, then the symbol Sn, the name Tin, and 118.71 at the bottom. What does the 50 tell you? Answer: Every tin atom has 50 protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 50 at the top, then the symbol Sn, the name Tin, and 118.71 at the bottom. Which of these is the atomic number? Answer: 50. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • An element box shows 53 at the top, then the symbol I, the name Iodine, and 126.90 at the bottom. How many electrons does a neutral atom of this element have? Answer: 53. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 53 at the top, then the symbol I, the name Iodine, and 126.90 at the bottom. What does the 126.90 tell you? Answer: The average mass of iodine atoms, in atomic mass units. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 53 at the top, then the symbol I, the name Iodine, and 126.90 at the bottom. Which of these is the atomic mass? Answer: 126.90. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 79 at the top, then the symbol Au, the name Gold, and 196.97 at the bottom. How many protons does one atom of this element have? Answer: 79. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 79 at the top, then the symbol Au, the name Gold, and 196.97 at the bottom. Round the atomic mass to a whole number. What mass number do you get? Answer: 197. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 79 at the top, then the symbol Au, the name Gold, and 196.97 at the bottom. What does the 79 tell you? Answer: Every gold atom has 79 protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 82 at the top, then the symbol Pb, the name Lead, and 207.2 at the bottom. Round the atomic mass to a whole number. What mass number do you get? Answer: 207. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An element box shows 82 at the top, then the symbol Pb, the name Lead, and 207.2 at the bottom. What does the 207.2 tell you? Answer: The average mass of lead atoms, in atomic mass units. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • An element box shows 82 at the top, then the symbol Pb, the name Lead, and 207.2 at the bottom. Which of these is the atomic mass? Answer: 207.2. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.

Protons, neutrons and electrons 108

  • A neutral atom of argon has a mass number of 40 and 22 neutrons. How many electrons does it have? Answer: 18. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of beryllium has a mass number of 9 and 5 neutrons. How many electrons does it have? Answer: 4. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of calcium has a mass number of 40 and 20 neutrons. How many electrons does it have? Answer: 20. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of carbon has a mass number of 12 and 6 neutrons. How many electrons does it have? Answer: 6. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of chromium has a mass number of 52 and 28 neutrons. How many electrons does it have? Answer: 24. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of germanium has a mass number of 74 and 42 neutrons. How many electrons does it have? Answer: 32. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of helium has a mass number of 4 and 2 neutrons. How many electrons does it have? Answer: 2. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of iron has a mass number of 56 and 30 neutrons. How many electrons does it have? Answer: 26. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of krypton has a mass number of 84 and 48 neutrons. How many electrons does it have? Answer: 36. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of magnesium has a mass number of 24 and 12 neutrons. How many electrons does it have? Answer: 12. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of neon has a mass number of 20 and 10 neutrons. How many electrons does it have? Answer: 10. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of nickel has a mass number of 58 and 30 neutrons. How many electrons does it have? Answer: 28. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of oxygen has a mass number of 16 and 8 neutrons. How many electrons does it have? Answer: 8. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of selenium has a mass number of 80 and 46 neutrons. How many electrons does it have? Answer: 34. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of silicon has a mass number of 28 and 14 neutrons. How many electrons does it have? Answer: 14. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of sulfur has a mass number of 32 and 16 neutrons. How many electrons does it have? Answer: 16. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of titanium has a mass number of 48 and 26 neutrons. How many electrons does it have? Answer: 22. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • A neutral atom of zinc has a mass number of 64 and 34 neutrons. How many electrons does it have? Answer: 30. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Aluminum (Al) has atomic number 13 and atomic mass 26.982. Round the mass to a whole number. How many neutrons does that atom have? Answer: 14. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 3 protons and 4 neutrons. Which element is it? Answer: Lithium. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 6 protons and 6 neutrons. Which element is it? Answer: Carbon. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 9 protons and 10 neutrons. Which element is it? Answer: Fluorine. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 12 protons and 12 neutrons. Which element is it? Answer: Magnesium. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 15 protons and 16 neutrons. Which element is it? Answer: Phosphorus. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 18 protons and 22 neutrons. Which element is it? Answer: Argon. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 21 protons and 24 neutrons. Which element is it? Answer: Scandium. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 24 protons and 28 neutrons. Which element is it? Answer: Chromium. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 27 protons and 32 neutrons. Which element is it? Answer: Cobalt. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 30 protons and 34 neutrons. Which element is it? Answer: Zinc. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 33 protons and 42 neutrons. Which element is it? Answer: Arsenic. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom has 36 protons and 48 neutrons. Which element is it? Answer: Krypton. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of aluminum has 13 protons and 14 neutrons. What is its mass number? Answer: 27. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of aluminum has a mass number of 27 and 14 neutrons. How many protons does it have? Answer: 13. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of arsenic has a mass number of 75 and 42 neutrons. How many protons does it have? Answer: 33. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of beryllium has 4 protons and 5 neutrons. What is its mass number? Answer: 9. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of boron has a mass number of 11 and 6 neutrons. How many protons does it have? Answer: 5. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of bromine has a mass number of 79 and 44 neutrons. How many protons does it have? Answer: 35. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of chlorine has a mass number of 35 and 18 neutrons. How many protons does it have? Answer: 17. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of cobalt has a mass number of 59 and 32 neutrons. How many protons does it have? Answer: 27. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of copper has a mass number of 63 and 34 neutrons. How many protons does it have? Answer: 29. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of fluorine has a mass number of 19 and 10 neutrons. How many protons does it have? Answer: 9. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of gallium has 31 protons and 38 neutrons. What is its mass number? Answer: 69. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of gallium has a mass number of 69 and 38 neutrons. How many protons does it have? Answer: 31. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of hydrogen has 1 proton and no neutrons. What is its mass number? Answer: 1. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of hydrogen has a mass number of 1 and 0 neutrons. How many protons does it have? Answer: 1. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of lithium has a mass number of 7 and 4 neutrons. How many protons does it have? Answer: 3. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of manganese has 25 protons and 30 neutrons. What is its mass number? Answer: 55. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of manganese has a mass number of 55 and 30 neutrons. How many protons does it have? Answer: 25. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of neon has 10 protons and 10 neutrons. What is its mass number? Answer: 20. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of nickel has 28 protons and 30 neutrons. What is its mass number? Answer: 58. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of nitrogen has 7 protons and 7 neutrons. What is its mass number? Answer: 14. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of nitrogen has a mass number of 14 and 7 neutrons. How many protons does it have? Answer: 7. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of phosphorus has a mass number of 31 and 16 neutrons. How many protons does it have? Answer: 15. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of potassium has 19 protons and 20 neutrons. What is its mass number? Answer: 39. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of potassium has a mass number of 39 and 20 neutrons. How many protons does it have? Answer: 19. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of scandium has a mass number of 45 and 24 neutrons. How many protons does it have? Answer: 21. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of selenium has 34 protons and 46 neutrons. What is its mass number? Answer: 80. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of sodium has a mass number of 23 and 12 neutrons. How many protons does it have? Answer: 11. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of sulfur has 16 protons and 16 neutrons. What is its mass number? Answer: 32. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of titanium has 22 protons and 26 neutrons. What is its mass number? Answer: 48. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • An atom of vanadium has a mass number of 51 and 28 neutrons. How many protons does it have? Answer: 23. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Argon (Ar) has atomic number 18 and atomic mass 39.95. Round the mass to a whole number. How many neutrons does that atom have? Answer: 22. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Arsenic (As) has atomic number 33 and atomic mass 74.922. Round the mass to a whole number. How many neutrons does that atom have? Answer: 42. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Beryllium (Be) has atomic number 4 and atomic mass 9.0122. Round the mass to a whole number. How many neutrons does that atom have? Answer: 5. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Boron (B) has atomic number 5 and atomic mass 10.81. Round the mass to a whole number. How many neutrons does that atom have? Answer: 6. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Bromine (Br) has atomic number 35 and atomic mass 79.904. Round the mass to a whole number. How many neutrons does that atom have? Answer: 45. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Calcium (Ca) has atomic number 20 and atomic mass 40.078. Round the mass to a whole number. How many neutrons does that atom have? Answer: 20. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Carbon (C) has atomic number 6 and atomic mass 12.011. Round the mass to a whole number. How many neutrons does that atom have? Answer: 6. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Chlorine (Cl) has atomic number 17 and atomic mass 35.45. Round the mass to a whole number. How many neutrons does that atom have? Answer: 18. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Chromium (Cr) has atomic number 24 and atomic mass 51.996. Round the mass to a whole number. How many neutrons does that atom have? Answer: 28. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Cobalt (Co) has atomic number 27 and atomic mass 58.933. Round the mass to a whole number. How many neutrons does that atom have? Answer: 32. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Copper (Cu) has atomic number 29 and atomic mass 63.546. Round the mass to a whole number. How many neutrons does that atom have? Answer: 35. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Fluorine (F) has atomic number 9 and atomic mass 18.998. Round the mass to a whole number. How many neutrons does that atom have? Answer: 10. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Gallium (Ga) has atomic number 31 and atomic mass 69.723. Round the mass to a whole number. How many neutrons does that atom have? Answer: 39. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Germanium (Ge) has atomic number 32 and atomic mass 72.630. Round the mass to a whole number. How many neutrons does that atom have? Answer: 41. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Helium (He) has atomic number 2 and atomic mass 4.0026. Round the mass to a whole number. How many neutrons does that atom have? Answer: 2. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Hydrogen (H) has atomic number 1 and atomic mass 1.0080. Round the mass to a whole number. How many neutrons does that atom have? Answer: 0. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Iron (Fe) has atomic number 26 and atomic mass 55.845. Round the mass to a whole number. How many neutrons does that atom have? Answer: 30. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Krypton (Kr) has atomic number 36 and atomic mass 83.798. Round the mass to a whole number. How many neutrons does that atom have? Answer: 48. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Lithium (Li) has atomic number 3 and atomic mass 6.94. Round the mass to a whole number. How many neutrons does that atom have? Answer: 4. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Magnesium (Mg) has atomic number 12 and atomic mass 24.305. Round the mass to a whole number. How many neutrons does that atom have? Answer: 12. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Manganese (Mn) has atomic number 25 and atomic mass 54.938. Round the mass to a whole number. How many neutrons does that atom have? Answer: 30. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Neon (Ne) has atomic number 10 and atomic mass 20.180. Round the mass to a whole number. How many neutrons does that atom have? Answer: 10. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Nickel (Ni) has atomic number 28 and atomic mass 58.693. Round the mass to a whole number. How many neutrons does that atom have? Answer: 31. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Nitrogen (N) has atomic number 7 and atomic mass 14.007. Round the mass to a whole number. How many neutrons does that atom have? Answer: 7. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Oxygen (O) has atomic number 8 and atomic mass 15.999. Round the mass to a whole number. How many neutrons does that atom have? Answer: 8. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Phosphorus (P) has atomic number 15 and atomic mass 30.974. Round the mass to a whole number. How many neutrons does that atom have? Answer: 16. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Potassium (K) has atomic number 19 and atomic mass 39.098. Round the mass to a whole number. How many neutrons does that atom have? Answer: 20. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Scandium (Sc) has atomic number 21 and atomic mass 44.956. Round the mass to a whole number. How many neutrons does that atom have? Answer: 24. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Selenium (Se) has atomic number 34 and atomic mass 78.971. Round the mass to a whole number. How many neutrons does that atom have? Answer: 45. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Silicon (Si) has atomic number 14 and atomic mass 28.085. Round the mass to a whole number. How many neutrons does that atom have? Answer: 14. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Sodium (Na) has atomic number 11 and atomic mass 22.990. Round the mass to a whole number. How many neutrons does that atom have? Answer: 12. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Sulfur (S) has atomic number 16 and atomic mass 32.06. Round the mass to a whole number. How many neutrons does that atom have? Answer: 16. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Titanium (Ti) has atomic number 22 and atomic mass 47.867. Round the mass to a whole number. How many neutrons does that atom have? Answer: 26. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Vanadium (V) has atomic number 23 and atomic mass 50.942. Round the mass to a whole number. How many neutrons does that atom have? Answer: 28. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of boron-11 (atomic number 5)? Answer: 5 protons, 6 neutrons, 5 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of bromine-79 (atomic number 35)? Answer: 35 protons, 44 neutrons, 35 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of calcium-40 (atomic number 20)? Answer: 20 protons, 20 neutrons, 20 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of chlorine-35 (atomic number 17)? Answer: 17 protons, 18 neutrons, 17 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of copper-63 (atomic number 29)? Answer: 29 protons, 34 neutrons, 29 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of germanium-74 (atomic number 32)? Answer: 32 protons, 42 neutrons, 32 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of helium-4 (atomic number 2)? Answer: 2 protons, 2 neutrons, 2 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of iron-56 (atomic number 26)? Answer: 26 protons, 30 neutrons, 26 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of oxygen-16 (atomic number 8)? Answer: 8 protons, 8 neutrons, 8 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of silicon-28 (atomic number 14)? Answer: 14 protons, 14 neutrons, 14 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of sodium-23 (atomic number 11)? Answer: 11 protons, 12 neutrons, 11 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Which row is right for a neutral atom of vanadium-51 (atomic number 23)? Answer: 23 protons, 28 neutrons, 23 electrons. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Zinc (Zn) has atomic number 30 and atomic mass 65.38. Round the mass to a whole number. How many neutrons does that atom have? Answer: 35. Source: NIST, Atomic Weights and Isotopic Compositions; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.

Find it by group and period 61

  • How many elements are in group 1 of the periodic table? Answer: 7. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in group 2 of the periodic table? Answer: 6. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in group 17 of the periodic table? Answer: 6. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in group 18 of the periodic table? Answer: 7. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in period 1 of the periodic table? Answer: 2. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in period 2 of the periodic table? Answer: 8. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in period 3 of the periodic table? Answer: 8. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in period 4 of the periodic table? Answer: 18. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many elements are in period 6 of the periodic table? Answer: 32. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is aluminum (Al, atomic number 13)? Answer: Group 13, period 3. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is argon (Ar, atomic number 18)? Answer: Group 18, period 3. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is beryllium (Be, atomic number 4)? Answer: Group 2, period 2. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is bromine (Br, atomic number 35)? Answer: Group 17, period 4. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is calcium (Ca, atomic number 20)? Answer: Group 2, period 4. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is carbon (C, atomic number 6)? Answer: Group 14, period 2. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is chlorine (Cl, atomic number 17)? Answer: Group 17, period 3. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is neon (Ne, atomic number 10)? Answer: Group 18, period 2. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is oxygen (O, atomic number 8)? Answer: Group 16, period 2. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is phosphorus (P, atomic number 15)? Answer: Group 15, period 3. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is silicon (Si, atomic number 14)? Answer: Group 14, period 3. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is silver (Ag, atomic number 47)? Answer: Group 11, period 5. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is sodium (Na, atomic number 11)? Answer: Group 1, period 3. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, in which group and period is zinc (Zn, atomic number 30)? Answer: Group 12, period 4. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 1, period 1? Answer: Hydrogen. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 1, period 2? Answer: Lithium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 1, period 4? Answer: Potassium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 2, period 3? Answer: Magnesium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 2, period 4? Answer: Calcium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 4, period 4? Answer: Titanium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 8, period 4? Answer: Iron. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 10, period 4? Answer: Nickel. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 11, period 4? Answer: Copper. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 11, period 5? Answer: Silver. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 11, period 6? Answer: Gold. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 12, period 6? Answer: Mercury. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 13, period 2? Answer: Boron. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 14, period 3? Answer: Silicon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 14, period 5? Answer: Tin. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 14, period 6? Answer: Lead. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 15, period 2? Answer: Nitrogen. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 16, period 3? Answer: Sulfur. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 17, period 2? Answer: Fluorine. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 17, period 5? Answer: Iodine. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 18, period 1? Answer: Helium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Using group numbers 1 to 18, which element sits in group 18, period 4? Answer: Krypton. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element has exactly one more proton than argon? Answer: Potassium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element has exactly one more proton than calcium? Answer: Scandium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element has exactly one more proton than fluorine? Answer: Neon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element has exactly one more proton than helium? Answer: Lithium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element has exactly one more proton than magnesium? Answer: Aluminum. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element has exactly one more proton than neon? Answer: Sodium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below aluminum in the same group? Answer: Gallium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below carbon in the same group? Answer: Silicon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below chlorine in the same group? Answer: Bromine. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below copper in the same group? Answer: Silver. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below fluorine in the same group? Answer: Chlorine. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below lithium in the same group? Answer: Sodium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below magnesium in the same group? Answer: Calcium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below neon in the same group? Answer: Argon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below nitrogen in the same group? Answer: Phosphorus. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Which element is directly below oxygen in the same group? Answer: Sulfur. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.

Metal, nonmetal or metalloid 62

  • Copper is described as ductile. What does ductile mean? Answer: It can be drawn out into a wire. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Hydrogen sits at the top of group 1. Which statement about it is right? Answer: It is a nonmetal and is not counted as an alkali metal. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • In most textbooks, which columns of the table hold the transition metals? Answer: Groups 3 to 12. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Is aluminum (Al) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is antimony (Sb) a metal, a nonmetal or a metalloid? Answer: Metalloid. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is arsenic (As) a metal, a nonmetal or a metalloid? Answer: Metalloid. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is boron (B) a metal, a nonmetal or a metalloid? Answer: Metalloid. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is calcium (Ca) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is carbon (C) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is chlorine (Cl) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is copper (Cu) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is germanium (Ge) a metal, a nonmetal or a metalloid? Answer: Metalloid. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is gold (Au) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is hydrogen (H) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is iron (Fe) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is magnesium (Mg) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is neon (Ne) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is nitrogen (N) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is oxygen (O) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is phosphorus (P) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is potassium (K) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is silicon (Si) a metal, a nonmetal or a metalloid? Answer: Metalloid. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is sodium (Na) a metal, a nonmetal or a metalloid? Answer: Metal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is sulfur (S) a metal, a nonmetal or a metalloid? Answer: Nonmetal. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Is tellurium (Te) a metal, a nonmetal or a metalloid? Answer: Metalloid. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Metals are described as malleable. What does malleable mean? Answer: Able to be bent or hammered into shape without breaking. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Three of these elements are alkali metals. Which one is not? Answer: Calcium. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Three of these elements are alkaline earth metals. Which one is not? Answer: Sodium. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Three of these elements are halogens. Which one is not? Answer: Sulfur. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Three of these elements are metalloids. Which one is not? Answer: Phosphorus. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Three of these elements are noble gases. Which one is not? Answer: Nitrogen. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Three of these elements are nonmetals. Which one is not? Answer: Silicon. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Three of these elements are transition metals. Which one is not? Answer: Aluminum. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Two rows are drawn underneath the main table. What is the top one of those rows called? Answer: The lanthanides. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Using group numbers 1 to 18, which group holds the alkali metals? Answer: 1. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Using group numbers 1 to 18, which group holds the alkaline earth metals? Answer: 2. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Using group numbers 1 to 18, which group holds the chalcogens? Answer: 16. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Using group numbers 1 to 18, which group holds the halogens? Answer: 17. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Using group numbers 1 to 18, which group holds the noble gases? Answer: 18. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Using group numbers 1 to 18, which group holds the pnictogens? Answer: 15. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Which columns hold the main-group (representative) elements? Answer: Groups 1, 2 and 13 to 18. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Which description fits a metalloid? Answer: It conducts heat and electricity moderately well and shares traits with both metals and nonmetals. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Which named family does argon (Ar) belong to? Answer: Noble gases. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does barium (Ba) belong to? Answer: Alkaline earth metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does bromine (Br) belong to? Answer: Halogens. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does calcium (Ca) belong to? Answer: Alkaline earth metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does cesium (Cs) belong to? Answer: Alkali metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does fluorine (F) belong to? Answer: Halogens. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does helium (He) belong to? Answer: Noble gases. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does iodine (I) belong to? Answer: Halogens. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does iron (Fe) belong to? Answer: Transition metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does lithium (Li) belong to? Answer: Alkali metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does magnesium (Mg) belong to? Answer: Alkaline earth metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does nickel (Ni) belong to? Answer: Transition metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does potassium (K) belong to? Answer: Alkali metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does rubidium (Rb) belong to? Answer: Alkali metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does silver (Ag) belong to? Answer: Transition metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does strontium (Sr) belong to? Answer: Alkaline earth metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does titanium (Ti) belong to? Answer: Transition metals. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which named family does xenon (Xe) belong to? Answer: Noble gases. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Which set of properties describes most metals? Answer: Shiny, malleable, and good conductors of heat and electricity. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Which set of properties describes most nonmetals? Answer: Dull in appearance and poor conductors of heat and electricity. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.

How the table is organized 34

  • Aluminum is in group 13. How many valence electrons does an aluminum atom have? Answer: 3. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • The atomic mass unit is defined as one twelfth of the mass of an atom of which isotope? Answer: Carbon-12. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • The atomic number of an element is equal to the number of what? Answer: Protons in the nucleus. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • Calcium is in group 2. How many valence electrons does a calcium atom have? Answer: 2. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Carbon is in group 14. How many valence electrons does a carbon atom have? Answer: 4. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Chlorine is in group 17. How many valence electrons does a chlorine atom have? Answer: 7. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Fluorine is in group 17. How many valence electrons does a fluorine atom have? Answer: 7. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Helium is in group 18. How many valence electrons does a helium atom have? Answer: 2. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • How did Mendeleev order the elements in his 1869 table? Answer: By increasing atomic mass. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • How many elements are on the current periodic table? Answer: 118. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • How many groups does the periodic table have? Answer: 18. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • How many periods does the periodic table have? Answer: 7. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • In a neutral atom, the number of electrons equals the number of what? Answer: Protons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • Magnesium is in group 2. How many valence electrons does a magnesium atom have? Answer: 2. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • The modern periodic table lists the elements in order of increasing what? Answer: Atomic number. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Neon is in group 18. How many valence electrons does a neon atom have? Answer: 8. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Nitrogen is in group 15. How many valence electrons does a nitrogen atom have? Answer: 5. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Oxygen is in group 16. How many valence electrons does an oxygen atom have? Answer: 6. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • The periodic law says the properties of the elements repeat in a regular pattern when the elements are ordered by what? Answer: Their atomic numbers. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Phosphorus is in group 15. How many valence electrons does a phosphorus atom have? Answer: 5. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Potassium is in group 1. How many valence electrons does a potassium atom have? Answer: 1. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Silicon is in group 14. How many valence electrons does a silicon atom have? Answer: 4. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Sodium is in group 1. How many valence electrons does a sodium atom have? Answer: 1. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Two atoms have the same number of protons but different numbers of neutrons. What are they called? Answer: Isotopes of the same element. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • What are valence electrons? Answer: The electrons in the outermost shell of an atom. Source: OpenStax Chemistry 2e, section 6.4, Electronic Structure of Atoms. Read 2026-09-19.
  • What do elements in the same group have in common? Answer: The same number of valence electrons, so they react in similar ways. Source: OpenStax Chemistry 2e, section 6.4, Electronic Structure of Atoms. Read 2026-09-19.
  • What does the mass number of an atom count? Answer: Protons plus neutrons. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • What is a horizontal row of the periodic table called? Answer: A period. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • What is a vertical column of the periodic table called? Answer: A group. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Which calculation gives the number of neutrons in an atom? Answer: Mass number minus atomic number. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • Which chemist published a periodic table in 1869 and left gaps for elements not yet found? Answer: Dimitri Mendeleev. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Which is the correct way to write the symbol for cobalt? Answer: Co, a capital C then a small o. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.
  • Which two elements, found in 1875 and 1886, matched gaps Mendeleev had left in his table? Answer: Gallium and germanium. Source: OpenStax Chemistry 2e, section 2.5, The Periodic Table. Read 2026-09-19.
  • Why is the atomic mass on the table usually a decimal and not a whole number? Answer: It is a weighted average of the masses of the element's natural isotopes. Source: OpenStax Chemistry 2e, section 2.3, Atomic Structure and Symbolism. Read 2026-09-19.

Scavenger hunt clues 30

  • Scavenger hunt: add the atomic numbers of hydrogen and helium. Which element has that atomic number? Answer: Lithium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the alkali metal in period 4. Answer: Potassium. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the alkaline earth metal in period 2. Answer: Beryllium. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the element at the bottom of group 2. Answer: Radium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element directly above gold. Answer: Silver. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element in the same group as carbon and the same period as calcium. Answer: Germanium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element in the same group as oxygen and the same period as sodium. Answer: Sulfur. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element in the very last box of the table, group 18 of period 7. Answer: Oganesson. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element whose atomic number equals the number of groups on the table. Answer: Argon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element whose atomic number equals the number of periods on the table. Answer: Nitrogen. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the element with exactly twice as many protons as oxygen. Answer: Sulfur. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the first element of period 4. Answer: Potassium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the group 18 element in the same period as calcium. Answer: Krypton. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the halogen in period 4. Answer: Bromine. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the halogen with the fewest protons. Answer: Fluorine. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the last element of period 2. Answer: Neon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the noble gas in period 3. Answer: Argon. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: find the noble gas that has only 2 valence electrons. Answer: Helium. Source: PubChem periodic table, electron configurations; OpenStax Chemistry 2e, section 6.4. Read 2026-09-19.
  • Scavenger hunt: find the only metalloid in period 2. Answer: Boron. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the only metalloid in period 3. Answer: Silicon. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the only nonmetal in group 1. Answer: Hydrogen. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: find the period 4 element in group 8. Answer: Iron. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: how many elements in period 2 are gases at room temperature? Answer: 4. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: how many elements in period 3 are gases at room temperature? Answer: 2. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: in which pair does the first element have a larger atomic mass than the one after it? Answer: Argon and potassium. Source: IUPAC CIAAW, Abridged Standard Atomic Weights 2024; method from OpenStax Chemistry 2e, section 2.3. Read 2026-09-19.
  • Scavenger hunt: reading from atomic number 1 upward, which is the first metal you reach? Answer: Lithium. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: which element starts a new period straight after neon? Answer: Sodium. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: which period has only two elements? Answer: Period 1. Source: IUPAC Periodic Table of the Elements, 4 May 2022. Read 2026-09-19.
  • Scavenger hunt: which two elements are liquids at room temperature? Answer: Bromine and mercury. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.
  • Scavenger hunt: which two elements are the metalloids of period 4? Answer: Germanium and arsenic. Source: PubChem periodic table, element categories and standard states. Read 2026-09-19.

How this list was compiled: Questions, wrong choices and explanations were written for this site, most of them built from checked tables. Names, symbols, atomic numbers, groups and periods come from this site's 118-element table, which follows the IUPAC Periodic Table of the Elements dated 4 May 2022, https://iupac.org/what-we-do/periodic-table-of-elements/; every group and period was also confirmed against the position worked out from the atomic number, and every name, symbol and category against the PubChem periodic table, https://pubchem.ncbi.nlm.nih.gov/rest/pug/periodictable/JSON, which also supplies the standard states and electron configurations. Atomic masses are the IUPAC CIAAW Abridged Standard Atomic Weights 2024, https://ciaaw.org/abridged-atomic-weights.htm. Natural isotopes and their abundances are from NIST Atomic Weights and Isotopic Compositions, https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=&ascii=html&isotype=some. Definitions and the history questions were checked phrase by phrase against saved copies of OpenStax Chemistry 2e sections 2.3, 2.5 and 6.4, https://openstax.org/books/chemistry-2e/pages/2-5-the-periodic-table. All five sources were read on 2026-09-19. Licence: own work

How it works

This periodic table worksheet is a bank of 337 element questions that make you read the table instead of reciting it. Work out what the numbers in an element box mean, count protons, neutrons and electrons, find an element from its group and period, and sort metals from nonmetals. Answer on screen, or print a write-in sheet, a scavenger hunt and the key.

Read the full guide

Six sets, from a first look to a review

Read an element box works as a getting to know the elements worksheet: it shows a box such as 11, Na, Sodium, 22.990 and asks what each number tells you. Protons, neutrons and electrons covers elements 1 to 36. Two sets send you across the table, by position and by family. How the table is organized is an organization of the periodic table worksheet: periods, groups, valence electrons and Mendeleev. Leave the topic menu on every topic for a periodic table review worksheet.

The rounding rule, and where it bends

Most classes find neutrons by rounding the atomic mass to a whole number and taking away the atomic number. Every neutron question states that rule. The note after the answer compares the result with real atoms. Sodium comes out exactly, because sodium-23 is the only natural isotope NIST lists. Copper does not: 63.546 rounds to 64, yet natural copper is a mix of copper-63 and copper-65. Six of the first 36 elements bend the rule this way.

Printing: two write-in sheets, a table and a key

Under the quiz are four sheets, each with its own print button. The printable periodic table worksheet has a line to write on under every row: twelve elements to fill in, six atoms to work backward from and two questions to answer in a sentence. The periodic table scavenger hunt worksheet has 18 clues. The reference table lists elements 1 to 36 with mass, group, period and family, and the key covers both sheets. The whole topic, in the Sheet to print menu, puts one set of multiple-choice questions on paper with a bubble sheet and a short key.

  • New to the table? Do Read an element box, then How the table is organized: an intro to periodic table worksheet that needs no calculator.
  • The four sheets are this page's periodic table of elements printable worksheets. Hand out the reference table with the write-in sheet, so nobody needs a wall chart.
  • For the scavenger hunt, bring a full table that shows families and states at room temperature. Clue 17 asks for the two liquids.
  • A wrong answer waits in the missed pile until you get it right. Clear the pile the next day to see if the method stuck.

Questions and answers

Does this periodic table worksheet come with answers?

Yes. It is a periodic table worksheet and answers in one place: each of the 337 questions shows the right choice and the working once you check it, the full list under the quiz gives every answer, and the two write-in sheets have their own key. The page does not hold the key to a worksheet from your textbook or another publisher.

Can I save a periodic table worksheet pdf?

Yes. Press Print this sheet or Print, then choose Save as PDF in your browser's print window. That gives you a periodic table of elements worksheet pdf. Save the key the same way for a set of periodic table worksheets with answers pdf files.

Which set fits a first lesson on the table?

For an introduction to the periodic table worksheet, start with the element box set. A get to know the elements worksheet covers the same ground. An organizing the periodic table worksheet, or a basics of the periodic table worksheet, asks about periods, groups and families, the fifth set here. For an introducing the periodic table worksheet that mixes both, do each in turn. The proton and neutron set suits a chemistry elements worksheet.

My book calls it a periodic chart and shows other masses. Does that matter?

No. Periodic chart is another name for the same table, so a periodic chart worksheet covers the same ground. Masses here are the IUPAC abridged standard atomic weights of 2024, so you may see 22.990 where your chart prints 22.99. Every question that needs a mass states it, so no answer depends on the chart on your wall.

How is this different from the periodic table quiz?

The periodic table quiz and the first 20 elements quiz ask where an element sits on a blank table, and the element symbols quiz asks what it is called. This page hands you the table's numbers and asks you to work something out: a neutron count, a group, a family. Once the layout is familiar, use this page as a periodic table practice worksheet.

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