Admin Table of Contents
- 1 What Colour flame is produced when the air hole is closed?
- 2 When lighting the Bunsen burner A Should the air hole be open or closed?
- 3 What colour is the flame on a Bunsen burner?
- 4 Why do we need to open the air hole of the Bunsen burner?
- 5 When the air hole is closed?
- 6 Why is it important to light a Bunsen burner with the air hole closed?
What Colour flame is produced when the air hole is closed?
yellow
When the air-hole is closed, however, there is less oxygen available. This results in incomplete combustion of the gas. The color of the flame changes to yellow and the flame is wavy. The yellow color is produced from particles of carbon (soot) in the flame which results from incomplete combustion of the methane gas.
When lighting the Bunsen burner A Should the air hole be open or closed?
Place the Bunsen burner on a heat-resistant mat 30 to 40 cm from the edge of the bench. Make sure the air hole is closed (unless you are lighting the gas with a piezo-electric lighter, in which case air hole should be half open).
What is the shape of the flame when the air hole is closed?
When the air hole is closed, the flame is yellow. However / But, when we let air mix with the gas the flame will turn blue….
| Air hole closed | Air hole open | |
|---|---|---|
| Shape of the flame | irregular | regular |
| Brightness of the flame | luminous | non-luminous |
| Temperature of the flame | lower | higher |
Which part of the Bunsen burner do you twist to open or close the air hole?
If your flame is hot and blue, twist the collar to close off the air flow and produce a yellow safety flame. Close the needle valve by turning it clockwise. Close the valve completely to cut off the gas supply.
What colour is the flame on a Bunsen burner?
pale blue flame
It burns with a pale blue flame, the primary flame, seen as a small inner cone, and a secondary, almost colourless flame, seen as a larger, outer cone, which results when the remaining gas is completely oxidized by the surrounding air. Bunsen burner.
Why do we need to open the air hole of the Bunsen burner?
Open Air Hole The air hole allows the air from the room to be drawn into the chimney and mix with the gas and therefore allow a plentiful supply of oxygen for the gas to react with. That results in complete combustion.
Why is a Bunsen burner flame yellow?
A blue natural gas flame colour is indicative of proper combustion and minimal wasted gas. A natural gas flame should be blue. Not having a natural gas blue flame color or an LPG (propane) blue flame color, and having yellow or red flames instead, could be indicative of an appliance problem.
Why is a Bunsen burner air hole?
There may also be a gas value on the Bunsen burner. The other critical component of a Bunsen burner is the air hole. This is located near the bottom of the chimney, just above the gas inlet. The air hole allows pre-mixing of air and gas before combustion occurs at the top of the chimney.
When the air hole is closed?
When the air hole is closed the natural gas can only mix with air at the mouth of the chimney. There is therefore not enough oxygen for complete combustion and incomplete combustion occurs. A bright luminous yellow flame occurs.
Why is it important to light a Bunsen burner with the air hole closed?
When you light a match always strike it away from you. The Bunsen will light to give a yellow safety flame. A lighted Bunsen Burner with its air holes closed giving a yellow safety flame. You must never use the yellow safety flame to heat something.