Bunsen Burner
Chemistry Lab
Getting to know your Bunsen burner
Part I
The Bunsen or Tirrell burner is commonly used in laboratory heating operations. While the details of construction vary among burners, each has a gas inlet located in the base, a vertical tube or barrel in which the gas is mixed with air, and an adjustable opening or ports in the base of the barrel to introduce air into the gas stream. The burner may have an adjustable needle valve to regulate the supply of gas, or adjusting the valve on the supply line may regulate the gas supply simply. The burner is always turned off at the gas valve, never at the needle valve.
Take your burner apart and examine it. Compare the parts with the drawing in Fig. 1-1.
Put the parts together again and note particularly how you can control the amount of air admitted near the base of the burner. In lighting the burner, partially close the ports at the base of the barrel, turn the gas full on, and hold the lighted match about 5 cm above the top of the burner. If you are using a torch lighter place the torch lighter next to and slightly above the burner, apply a downward pressure of the flint towards the plate and strike the lighter.
The gas may then be regulated until the flame has the desired height. If a very low flame is needed, the ports should be kept partly closed when the gas pressure is reduced. Otherwise the flame may "strike back" and burn inside the base of the barrel. If this happens, turn off the gas, decrease the amount of air admitted, and re-light.
Part II LUMINOUS FLAME
Relight the Bunsen burner. Close the airports or inlets as completely as possible and note the color and shape of the flame which is now luminous.
A Pass your hand quickly through the flame, which can be done without discomfort.
B Using crucible tongs, hold a dry porcelain-evaporating dish in the flame for a few seconds. Examine the dish and record your observations. After the
Getting to know your Bunsen burner
Part I
The Bunsen or Tirrell burner is commonly used in laboratory heating operations. While the details of construction vary among burners, each has a gas inlet located in the base, a vertical tube or barrel in which the gas is mixed with air, and an adjustable opening or ports in the base of the barrel to introduce air into the gas stream. The burner may have an adjustable needle valve to regulate the supply of gas, or adjusting the valve on the supply line may regulate the gas supply simply. The burner is always turned off at the gas valve, never at the needle valve.
Take your burner apart and examine it. Compare the parts with the drawing in Fig. 1-1.
Put the parts together again and note particularly how you can control the amount of air admitted near the base of the burner. In lighting the burner, partially close the ports at the base of the barrel, turn the gas full on, and hold the lighted match about 5 cm above the top of the burner. If you are using a torch lighter place the torch lighter next to and slightly above the burner, apply a downward pressure of the flint towards the plate and strike the lighter.
The gas may then be regulated until the flame has the desired height. If a very low flame is needed, the ports should be kept partly closed when the gas pressure is reduced. Otherwise the flame may "strike back" and burn inside the base of the barrel. If this happens, turn off the gas, decrease the amount of air admitted, and re-light.
Part II LUMINOUS FLAME
Relight the Bunsen burner. Close the airports or inlets as completely as possible and note the color and shape of the flame which is now luminous.
A Pass your hand quickly through the flame, which can be done without discomfort.
B Using crucible tongs, hold a dry porcelain-evaporating dish in the flame for a few seconds. Examine the dish and record your observations. After the