Bunsen Burner

Blueflame is non-luminous, and is difficult for a blue flame to be visible. Therefore, someone may put the hands into ablue flame accidentally.

However, yellow flame is luminous, and is visible readily.

Hence, we should change the flame to a yellow flame whenwe are not using Bunsen burner for a while.

When we use th Bunsen burner ,first we need to close the air hole.The colour of air hole closed is yellow,the colour of opened is blue.The shape of yellow flame is irregular,but blue flame is regular.However,brightness of the flame of the yellow flame is luminous ,but the blue flame is non-luminous.When the air hole is closed,it is quiet.When the air hole is opened,it become noisy.We use the blue flame that we can boil in a shorter period of time and the blue flame also is hotter.We use the Bunsen flame for heating.