2.3 - Mastering the Bunsen Burner Basics

What is the main function of the barrel on a Bunsen burner?

• To control the gas flow

• To mix gas with air

• To ignite the flame

• To support the burner

Answer explanation

The barrel of a Bunsen burner is designed to mix gas with air, allowing for proper combustion. This mixing is essential for achieving a clean and efficient flame, making it the correct answer.

Which part of the Bunsen burner is used to adjust the air supply?

• Base

• Barrel

• Collar

• Gas inlet

Answer explanation

The collar of the Bunsen burner is used to adjust the air supply. By rotating the collar, you can control the amount of air mixed with the gas, which affects the flame's characteristics.

What type of flame is produced when the air hole is closed?

• Blue flame

• Yellow flame

• Green flame

• Red flame

Answer explanation

When the air hole is closed, there is insufficient oxygen for complete combustion, resulting in a yellow flame. This flame indicates incomplete burning, producing soot and a lower temperature compared to a blue flame.

Why is a blue flame preferred over a yellow flame for heating?

• It is cooler

• It is more visible

• It is hotter and cleaner

• It is easier to control

Answer explanation

A blue flame indicates complete combustion, producing more heat and fewer pollutants compared to a yellow flame, which signifies incomplete combustion. Therefore, a blue flame is preferred for heating as it is hotter and cleaner.

What is the purpose of using a heat mat under a Bunsen burner?

• To prevent the table from getting hot

• To increase the flame temperature

• To stabilise the burner

• To reduce noise

Answer explanation

The purpose of using a heat mat under a Bunsen burner is to prevent the table from getting hot. This protects the surface from heat damage and ensures safety during experiments.

How can you increase the temperature of the flame on a Bunsen burner?

• Close the air hole

• Open the air hole

• Reduce the gas flow

• Use a larger burner

Answer explanation

Opening the air hole allows more oxygen to mix with the gas, resulting in a hotter flame. Closing it reduces oxygen, leading to a cooler flame. Therefore, to increase the flame temperature, you should open the air hole.

What should you do if the flame goes out unexpectedly?

• Immediately turn off the gas

• Relight the burner without checking

• Increase the gas flow

• Adjust the collar

Answer explanation

If the flame goes out unexpectedly, you should immediately turn off the gas to prevent any potential gas buildup, which can be dangerous. Relighting without checking or increasing gas flow can lead to hazardous situations.

Which part of the Bunsen burner connects to the gas supply?

• Barrel

• Collar

• Base

• Tube

Answer explanation

The tube of the Bunsen burner is the part that connects to the gas supply, allowing gas to flow into the burner for combustion. The other parts, like the barrel and collar, serve different functions.

What colour is the safety flame on a Bunsen burner?

• Blue

• Yellow

• Green

• Red

Answer explanation

The safety flame on a Bunsen burner is yellow. This flame indicates a cooler temperature and is used for safety when the burner is not in use, preventing accidental ignition.

Which of the following is NOT a part of a Bunsen burner?

• Barrel

• Collar

• Gas tap

• Base

Answer explanation

The gas tap is not a part of a Bunsen burner. The main components include the barrel, collar, and base, which are essential for its operation, while the gas tap is a separate fixture used to control gas flow.