What colour is a Bunsen burner flame?

Answer 1

The most efficient flame that a Bunsen burner can produce should be pale light blue, and almost invisible. A yellow or luminous flame should be avoided as it isn't as hot as the blue flame and leaves sut.

Answer 2

That depends on the amount of oxygen you supply to the flame (using the 'throat holes'), the more oxygen you supply, the completer the combustion and the hotter the flame will burn. If you supply little oxygen the flame will be yellow, if you supply the maximum, it will be blue.

Answer 3

A Bunsen burner flame is typically blue. The blue color indicates complete combustion of the gas.