MCQ on Combustion and Flame

CBSE/NCERT 8th Class MCQ CBSE/NCERT 8th Class MCQ on Science

21.Most common fire extinguisher which only works when things like wood and paper are on fire?

(A) Water

(B) Oil

(C) Foam

(D) Carbon dioxide


22.Why water is not suitable fires involving oil?

(A) Because the reaction between oil, water and air is highly exothermic

(B) Because oil is lighter than water so, it sinks below the oil and oil keeps burning on the top

(C) Because oil and water produce an enormous amount of heat

(D) None of the above


23.For fires involving electrical equipment’s and inflammable materials like petrol can be extinguished with help of …………..because it is heavier than oxygen and cover the fire like blanket.

(A) Fuel

(B) Water

(C) CO2

(D) All of the above


24.Which of the following statement is correct regarding CO2 as a fire extinguisher?

1. CO2 is the best extinguisher for electrical and inflammable materials like petrol.

2. It is heavier than oxygen and covers the fire like a blanket.

3.  It does not harm the electrical equipment.

4. it can be stored at high pressure in as a liquid in cylinders.

5. on releasing from the cylinder it expands enormously in volume and cools down the temperature of the fuel

(A) Option 1and 2

(B) Option 5

(C) Option 1, 2, 3, 4

(D) Option 1, 2, 3, 4, 5


25.Which of the following chemical gives off CO2?

(A) Sodium bicarbonate

(B) Potassium bicarbonate

(C) Both A and B

(D) None of the above


26.A process in which a large amount of heat and light is released in a very short span of time is called…………

(A) Spontaneous combustion

(B) Rapid combustion

(C) Self combustion

(D) None of the above


27.Which of the following is/are an example for rapid combustion?

(A) Fire in cracker factories

(B) Matchstick near the gas catches fire rapidly

(C) Fire in forest

(D) None of the above


28.Which of the following substance burns in air at room temperature?

(A) Phosphorous

(B) Sodium bicarbonate

(C) Potassium bicarbonate

(D) All of the above


29.The combustion in which a material suddenly burst into flames without the application of any apparent cause is called …………..

(A) Spontaneous combustion

(B) Rapid combustion

(C) Explosion combustion

(D) None of the above


30.Which of the following is/are an example/s of spontaneous combustion?

(A) Disastrous fire in coal mines

(B) Forest fire due to heat of sun or lightning strike

(C) Fire in cracker factories

(D) All of the above



21- (A) 22-(B) 23-(C) 24-(D) 25-(C) 26-(B) 27-(B) 28-(A) 29-(A) 30-(D)