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MCQ on Class 8 Combustion and Flame

Last updated on December 9th, 2023 at 08:45 pm

MCQ on Class 8 Combustion and Flame

 

Are you searching for MCQ on Class 8 Combustion and Flame then you are on the right place.

 

1. What is combustion?

  1. A cooling process involving water and oxygen
  2. A chemical reaction releasing heat when combined with oxygen
  3. A process that involves the formation of ice crystals
  4. A mechanical reaction occurring in the absence of air

Answer: B) A chemical reaction releasing heat when combined with oxygen

 

2. What is another term for a combustible substance?

  1. Extinguisher
  2. Inflammable material
  3. Catalyst
  4. Fuel

Answer: D) Fuel

 

3. What is the minimum temperature required for a material to catch fire called?

  1. Combustion temperature
  2. Melting point
  3. Ignition temperature
  4. Flashpoint

Answer: C) Ignition temperature

 

4. What type of substances easily catch fire due to their low ignition temperature?

  1. Non-flammable
  2. Inflammable
  3. Inert
  4. Exothermic

Answer: B) Inflammable

 

5. Which element is necessary for combustion to occur?

  1. Carbon
  2. Hydrogen
  3. Air
  4. Nitrogen

Answer: C) Air

 

6. What is the most common fire extinguishing agent used for combustible materials like paper and wood?

  1. Carbon dioxide
  2. Sand
  3. Water
  4. Foam

Answer: C) Water

 

7. Which measure is suitable for extinguishing fires caused by oil and petrol?

  1. Fire brigade stations
  2. Water
  3. Carbon dioxide extinguisher
  4. Blankets

Answer: C) Carbon dioxide extinguisher

 

8. What term is used for a rapid, uncontrolled release of light, heat, and sound?

  1. Spontaneous combustion
  2. Explosion
  3. Flame
  4. Rapid combustion

Answer: B) Explosion

 

9. What is the amount of heat generated on the combustion of 1 kg of fuel called?

  1. Thermal mass
  2. Heat index
  3. Calorific value
  4. Ignition rate

Answer: C) Calorific value

 

10. Which environmental effects are caused by burning fuel?

  1. Enhanced air quality
  2. Reduced greenhouse gas emissions
  3. Global warming, acid rain, and release of carbon particles
  4. Improved soil fertility

Answer: C) Global warming, acid rain, and release of carbon particles

 

11. What is the primary purpose of a fuel?

  1. To create light
  2. To produce electricity
  3. To provide energy through combustion
  4. To act as a fire extinguisher

Answer: c) To provide energy through combustion

 

12. Which of the following is a gaseous fuel commonly used in vehicles?

  1. Kerosene
  2. Diesel
  3. LPG
  4. Charcoal

Answer: c) LPG

 

13. What is the lowest temperature at which a substance can catch fire called?

  1. Boiling point
  2. Melting point
  3. Ignition temperature
  4. Flashpoint

Answer: c) Ignition temperature

 

14. Which of the following substances is considered inflammable?

  1. Water
  2. Sand
  3. Petrol
  4. Wood

Answer: c) Petrol

 

15. What is the purpose of a fire extinguisher?

  1. To increase the temperature of a fire
  2. To provide oxygen to the fire
  3. To disrupt the contact between air and the fire
  4. To create a larger flame

Answer: c) To disrupt the contact between air and the fire

 

16. Why is water a good substance for firefighting?

  1. Because it increases the temperature of the fuel
  2. Because it covers the fire like a blanket
  3. Because it is a fuel itself
  4. Because it produces more oxygen

Answer: b) Because it covers the fire like a blanket

 

17. In which situation should you NOT use water to extinguish a fire?

  1. When clothes catch fire
  2. When electrical equipment is on fire
  3. When burning wood
  4. When using a gas stove

Answer: b) When electrical equipment is on fire

 

18. What is the best extinguisher for fires involving electrical equipment and inflammable materials like petrol?

  1. Water
  2. Sand
  3. Carbon dioxide
  4. Oxygen

Answer: c) Carbon dioxide

 

19. Which type of combustion involves a sudden reaction with the release of heat, light, sound, and a large amount of gas?

  1. Rapid combustion
  2. Spontaneous combustion
  3. Controlled combustion
  4. Explosion

Answer: d) Explosion

 

20. What factor affects the rate of combustion by a combustible substance?

  1. The presence of oxygen
  2. The color of the substance
  3. The shape of the flame
  4. The density of the air

Answer: a) The presence of oxygen

 

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