Oxygen atomThe single large atom. Both hydrogen atoms are bonded to it.
Hydrogen atomOne of the two small atoms. Each is bonded to the oxygen.
Covalent bondA shared pair of electrons that holds two atoms together.
Partial negative chargeThe oxygen side of the molecule is slightly negative.
Partial positive chargeEach hydrogen atom is slightly positive.
Together 2
Hydrogen bondA weak pull from a hydrogen atom to another molecule's oxygen.
Water moleculeTwo hydrogen atoms bonded to one oxygen atom.
Electrons 2
Shared pair of electronsTwo electrons held by both atoms. Each shared pair is one covalent bond.
Lone pairTwo electrons that belong to the oxygen alone. It has two such pairs.
How this list was compiled: Every name and fact checked on 2026-10-01 and read again on 2026-10-02, a name kept only where two independent sources use it. (1) U.S. Geological Survey, Water Science School (public domain): Adhesion and Cohesion of Water, https://www.usgs.gov/special-topics/water-science-school/science/adhesion-and-cohesion-water , and Water, the Universal Solvent, https://www.usgs.gov/special-topics/water-science-school/science/water-universal-solvent (two hydrogen atoms on one side of an oxygen atom; a covalent bond; the oxygen side has a partial negative charge and the hydrogen side a partial positive charge; the positive side of one molecule attracts the negative side of another; hydrogen bonds drawn as dotted lines). (2) CK-12 Foundation through LibreTexts Chemistry, Introductory Chemistry 15.1 Structure of Water, https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/15%3A_Water/15.01%3A_Structure_of_Water ; 9.6 Single Covalent Bonds, https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/09%3A_Covalent_Bonding/9.06%3A_Single_Covalent_Bonds ; 9.19 Hydrogen Bonding, https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/09%3A_Covalent_Bonding/9.19%3A_Hydrogen_Bonding (oxygen pulls harder on the electrons shared in the covalent bonds; partial negative and partial positive charge, written with delta; bent because of the two lone pairs; a shared pair of electrons; a lone pair is not shared between atoms; the oxygen of water has two bonding pairs and two lone pairs; a hydrogen bond runs from the hydrogen atom of one molecule to a lone pair on the oxygen of a neighbor and is far weaker than a covalent bond). (3) Wikipedia, text only: Properties of water, https://en.wikipedia.org/wiki/Properties_of_water ; Covalent bond, https://en.wikipedia.org/wiki/Covalent_bond ; Lone pair, https://en.wikipedia.org/wiki/Lone_pair ; Hydrogen bond, https://en.wikipedia.org/wiki/Hydrogen_bond ; Chemical polarity, https://en.wikipedia.org/wiki/Chemical_polarity (two hydrogen atoms covalently bonded to one oxygen atom; shared pairs or bonding pairs; a lone pair is also called an unshared pair; two lone pairs on the oxygen; the oxygen partly negative and each hydrogen partly positive, written delta minus and delta plus; a bent, not linear, molecule; up to four hydrogen bonds per molecule, two taken on the lone pairs and two given by the hydrogen atoms; hydrogen bonds weaker than covalent bonds). (4) Chemguide, Intermolecular bonding: hydrogen bonds, https://www.chemguide.co.uk/atoms/bonding/hbond.html (each water molecule can form four hydrogen bonds, one on each lone pair and one through each hydrogen atom; a hydrogen bond is far weaker than a covalent bond). Licence: own work
The drawing: Drawn for this site on 2026-10-01 from plain geometry; nothing traced. Licence: own work
How it works
This water molecule diagram is unlabeled: every line ends in a blank. One molecule is at the top, five molecules joined by dotted lines are in the middle, and the electron pairs are at the foot.
Read the full guide
Water molecule, blank: label these nine parts
One molecule: oxygen atom, hydrogen atom, covalent bond, partial negative charge, partial positive charge. Five molecules: hydrogen bond, water molecule. Electron pairs: shared pair of electrons, lone pair. As a word bank, the list runs from the top of the sheet down.
Pairs that get swapped
A covalent bond is a stick inside one molecule. A hydrogen bond is a dotted line between two molecules. A shared pair is two dots where two circles overlap, and a lone pair is two dots on the large circle alone. The minus badge is the partial negative charge; each plus badge is a partial positive charge.
Seven parts are drawn more than once and marked once: a second hydrogen atom, stick or plus badge takes the first one's name.
When marking by hand, unshared pair is as right as lone pair, and bonding pair as right as shared pair of electrons.
Questions and answers
What holds water molecules together?
Hydrogen bonds. The slightly positive hydrogen side of one molecule attracts the slightly negative oxygen side of the next. On the sheet they are the four dotted lines of the middle drawing, each running from a small ball to a large one.
How many lone pairs does a water molecule have?
Two, both on the oxygen atom. In the bottom drawing they are the two pairs of dots at the top of the large circle, away from the hydrogen atoms. One pair is marked, and the other takes the same name.
How many electrons are shared in a water molecule?
Four. Each covalent bond is one shared pair, two electrons held by the oxygen atom and one hydrogen atom, and the molecule has two bonds. The other four of its eight outer electrons are the oxygen's two lone pairs.