Combustion Characteristics – Multiple Choice Questions

What is required for combustion to occur?

• Fuel and water

• Oxygen and nitrogen

• Fuel, oxygen, and heat

• Carbon dioxide and fuel

Which gas is a common product of complete combustion?

• Carbon monoxide

• Carbon dioxide

• Methane

• Hydrogen

What colour is a healthy gas flame during complete combustion?

• Yellow

• Blue

• Red

• Green

What does a yellow or orange flame usually indicate?

• High efficiency

• Incomplete combustion

• Low gas pressure

• Clean burning

Which of the following is a sign of incomplete combustion?

• Blue flame

• Soot deposits

• High oxygen levels

• Low carbon dioxide

What is the main danger of incomplete combustion?

• High heat output

• Carbon monoxide production

• Water vapour

• Excess oxygen

Which of the following is NOT a product of complete combustion of methane?

What is the chemical formula for methane?

• CO2

• H2O

• CH4

• C2H6

Which condition is essential to ensure complete combustion?

• Low temperature

• Correct air-to-gas ratio

• High humidity

• Low oxygen

What is the typical air-to-gas ratio for natural gas combustion?

• 5:1

• 50:1

• 10:1

• 20:1