Bunsen burner

The video tutorial explains the use of a device for heating and sterilizing, highlighting its simple, safe, and robust design. It describes how flammable gas, typically methane, is mixed with air at the base and ignited at the top. Adjusting the air hole affects the oxygen intake, producing either a hot blue flame or a cooler yellow flame, impacting combustion efficiency.

What characteristics make the design mentioned in the text simple, safe, and robust?

Explain the difference between a hot blue flame and a cooler yellow flame.