Why are bunsen burners blue

Learn more. Bunsen Burners and the Sun Ask Question. Asked 8 years, 6 months ago. Active 6 years, 11 months ago. Viewed 1k times. What element is being burned? Why does the sun glow yellow, and not blue-a Bunsen burner is much cooler and yet it burns blue. Is it because the relative size, or are they two different phenomena?

Improve this question. Add a comment. Active Oldest Votes. Combustion is complete and a blue flame is seen. This means there is more energy released. Combustion is incomplete and less energy is transferred. A blue flame from a Bunsen burner transfers more energy than a yellow Bunsen flame as complete combustion gives a blue flame. Incomplete combustion gives a yellow flame and so less energy is released. When combustion is incomplete, a yellow flame is seen. This is because a yellow flame produces a lot of soot.

Carbon monoxide, soot and water vapour are produced as well as carbon dioxide. The advantage of complete combustion is that more energy is released and no toxic gases or soot are produced. More energy is released during complete combustion than during incomplete combustion. Incomplete combustion occurs when a fuel burns in limited oxygen. This is the sudden production of vapour at the base of the liquid which propels boiling liquid, with some force, out of the open end of the tube.

Always ensure that there is no-one in front of your boiling tube, and remember that people do move around! If you need to boil a liquid, use a boiling tube which is wider and less prone to bumping than a test tube.

Always keep the boiling tube moving by gentle shaking. When it starts to boil remove the tube from the Bunsen flame until the boiling subsides.

If you need to keep the contents boiling you can briefly return the boiling tube to the flame. You will see this in the video. You will find that the use of an electric heating mantle may offer more control than a Bunsen burner. It is also safer as there is no naked flame so less chance of the contents catching fire. Home Chemistry Physics.

Practicals Home , Practicals A-Z. Cyberphysics - a web-based teaching aid - for students of physics, their teachers and parents Heating with a Bunsen Burner. Heating with a Bunsen Burner The Bunsen Burner is the most commonly used source of heat in school laboratories. Open Air Hole The Bunsen burner has a colar that you can turn to open or close an air hole. Closed Air Hole When the air hole is closed the natural gas can only mix with air at the mouth of the chimney.

Never heat anything using the luminous flame. Half-Closed Hole This is best for heating liquids.