Bunsen burner

The Bunsen burner, named after Robert Bunsen, is a laboratory device used to produce an open gas flame for heating, sterilizing, and combustion. The gas used can be natural gas (mostly methane) or liquefied gases like propane, butane, or a mixture of them.

The combustion process depends on the air-fuel mixture ratio. Less air results in incomplete combustion and a cooler flame, while a better air-fuel mixture leads to complete combustion and a hotter flame. The airflow is regulated by an adjustable slit at the base of the burner tube.

When the air holes are open, the flame burns hotter and appears blue, while closed air holes lead to a yellow, cooler flame. The yellow flame is due to incomplete combustion, producing soot. The blue flame is the result of complete combustion, often nearly invisible in certain backgrounds. The yellow flame is also known as the "safety flame" because of its brightness and tendency to leave carbon deposits.

The Bunsen burner is usually placed on a heat-resistant surface to protect the laboratory bench from the high temperatures and potential damage caused by the flame.