1.6
A Bunsen burner is an essential piece of laboratory equipment In this topic, you will learn that:
Using a Bunsen burner A mixture of liquid petroleum gas (LPG) or methane and air is used to produce a good flame for heating. The Bunsen burner has a collar that can be turned to open or close the air hole. The position of the collar controls how much air enters the burner and therefore how hot the flame is. If the hole is closed, less air can mix with the gas. This results in a yellow safety flame. If the collar hole is open, air mixes with the gas, allowing a hotter blue flame to burn. Match held to one side of top of burner
Hand below ˜ame
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Bunsen burner a piece of equipment used as a heat source in the laboratory
• the blue flame produces more heat than the yellow flame (over 1500°C). When alight but not being used for heating, the Bunsen burner should be left on the yellow (safety) flame, which is not as hot and is easy to see. The safety flame is always used when lighting the burner.
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Interactive 1.6 Lighting a Bunsen burner
• the yellow flame is called the safety flame because it is easier to see
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Video 1.6 How to use a Bunsen burner
• a Bunsen burner is used to heat things in the laboratory
What to do if there is a fire in the laboratory 1 Let the teacher know immediately (they will turn off the main gas tap if gas is involved). 2 The class fi re officer should take a message to the school administration as quickly as possible. 3 If the fi re is small, the teacher will use the fi re extinguisher. 4 Evacuate the area in an orderly manner.
Air hole closed
5 Check that everyone is safe.
Figure 1 The right way to light a Bunsen burner
Treating scalds and burns 1 Immediately run cold tap water on the scald or burn for at least 15 minutes. Do not use ice or very cold water. 2 Ask another student to tell your teacher about the scald or burn.
Figure 3 A scalded hand Air hole open
Air hole closed
3 Remove nearby clothing (unless it is stuck to the burnt area) and jewellery (such as watches, rings and bracelets) because burnt areas can swell quickly. 4 Try not to touch the area if possible. Do not use any creams.
Heating flame
Safety flame
Figure 2 Blue (heating) and yellow (safety) flames on the Bunsen burner
5 Seek medical attention if necessary.
Figure 4 A burnt hand
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