How it works
These are the parts of a Bunsen burner as a school lab names them, on two burners side by side: one with its air holes closed and one with them open, to show both flames.
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How it works
Gas comes through the rubber tubing into the gas inlet on the base. The gas valve sets how much flows. It rises up the barrel, pulling air in through the air holes, and burns at the top.
Two flames
Turn the collar to close the air holes and the flame burns yellow and sooty: the safety flame, easy to see. Open them and it burns blue and much hotter, the flame used for heating.
- Light the burner with the air holes closed, then open the collar to get the blue flame.
Questions and answers
What does the collar on a Bunsen burner do?
It is a sleeve on the barrel. Turning it opens or closes the air holes, which sets how much air mixes with the gas and so whether the flame is yellow or blue.
Why is the safety flame yellow?
With the air holes closed, too little air mixes with the gas, so it does not burn completely. Glowing unburned carbon makes the flame yellow, and it leaves soot.
What is the barrel of a Bunsen burner?
The upright metal tube. Gas and air mix inside it on the way up, and the flame burns at its top, well above the bench.