A science burner or what kind of burner?
'Rotary cup burner'
The purpose of a cross over tubes on a gas burner is so that the fire ignited from the main burner can make contact with the gas coming from the other burners.
A Bunsen burner is a convenient way to supply a small, controlled source of heat.
i think the purpose is to heat up water and/or other liquids.
It protects the tripod and the surface the busen burner is sitting on.
It is to prevent direct contact of the glass with the flame of the Bunsen burner. This lowers the possibility of the glass shattering when being heated Read more: What_is_the_purpose_of_the_wire_gauze_placed_over_a_bunsen_burner
The purpose of a cross over tubes on a gas burner is so that the fire ignited from the main burner can make contact with the gas coming from the other burners.
The purpose is the introduce the fuel gas in the burner.
safety feature of a gas burner
No recommended, oven glass is designed for a specific purpose. It you what to put 'glass' on a burner, buy a 'pan' or product for that purpose
i think the purpose is to heat up water and/or other liquids.
A Bunsen burner is a convenient way to supply a small, controlled source of heat.
Mix primary air and gas
Control of the ratio gas fuel/air in the burner.
An USB DVD burner is used to perform/fulfill a purpose. It is used so that the user of the burner can burn a copy onto another Compact Disc or USB drive.
They are to adjust the air/fuel mixture.
It protects the tripod and the surface the busen burner is sitting on.
The purpose is to control the combustible gas flow.