Bunsen burner
A Bunsen burner is a metal tube that burns gas to make a hot flame.
What is it for?
Scientists use it to heat things up, like boiling water or making a reaction go faster.
How to use it
A grown-up lights it with the air hole closed, which gives a gentle yellow flame. Opening the air hole makes a much hotter blue flame.
🥽 Safety tip: Tie back long hair, keep paper away, and switch back to the yellow flame when it is not in use, so everyone can see it is on.
Fun fact from Fizzy: It is named after Robert Bunsen, a German chemist who made it popular in the 1850s.
Why the flame changes colour
Fuel needs oxygen to burn. With the air hole closed, the gas does not get enough oxygen, so it burns with a wobbly yellow flame that leaves black soot on glassware. With the hole open, air mixes in before the gas burns, giving a hot, quiet blue flame.
The hottest part of the blue flame is just above the tip of the pale inner cone, where it can be well over 1,000 degrees Celsius.
Where you would see one
Bunsen burners are in most secondary school labs, connected to a gas tap on the bench. Many labs that work with bacteria now use electric heaters instead, but the Bunsen burner is still the classic lab flame.