Page 220 - Class 8th Chemistry Objective Questions and Answers Chapter - Combustion and Flame

Chapter - Combustion and Flame

1. In what form does wax burn in a candle?
(A) solid wax
(B) liquid wax
(C) wax vapor
(D) None of these
Answer :- (C) Vapor of wax

2. Which of the following substances is present in gunpowder?
(A) Sulphur
(B) Phosphorus
(C) Lead
(D) Bismuth
Answer :- (A) Sulphur

3. What will you do if there is a fire in the house?
(A) Will call the police
(B) Will call the fire brigade
(C) will run out
(D) Will go to the roof
Answer :- (B) Will call the fire brigade

4. Which of the following is not necessary for combustion?
(A) Presence of dark matter
(B) presence of air
(C) Obtaining heat of combustion
(D) Tendency of combustible material to catch fire immediately
Answer :- (D) Tendency of combustible material to catch fire immediately.

5. Which of the following substances is present at the end of the match stick?
(A) Mixture of red phosphorus and sand
(B) Mixture of antimony trisulphide and potassium chloride
(C) Mixture of white phosphorus and sand
(D) None of these
Answer: (B) Mixture of antimony trisulphide and potassium chloride.

6. What does the middle part of a candle flame look like?
(A) Red
(B) Yellow
(C) green
(D) black
Answer :- (B) Yellow

7. Which of the following fuels has the highest calorific value?
(A) wood
(B) Kerosene
(C) LPG
(D) Hydrogen 
Answer :- (D) Hydrogen

8. The best fire extinguisher to extinguish fire in electrical equipment is
(A) Petrol
(B) water
(C) Sand
(D) carbon dioxide
Answer :- (D) Carbon dioxide

9. How many zones are there in flame?
(A) 4
(B)3
(C)5
(D) 2
Answer :- (B)3

10. Which of the following is an example of spontaneous combustion?
(A) White phosphorus
(B) Burning of wood.
(C) Firecracker
(D) None of these.
Answer :- (A) White phosphorus

11. Which of the following is inflammable substance?
(A) wood
(B) Coal
(C) Petrol
(D) Stone.
Answer :- (C) Petrol

12. What is the temperature at which a substance starts burning called?
(A) combustion
(B) Flame
(C) inflammable
(D) Combustible substance.
Answer :- (A) Combustion

13. Which of the following is a non-combustible substance?
(A) wood
(B) Coal
(C) Petrol
(D) stone 
Answer :- (D) Stone

14. Oil fire is extinguished by which fire extinguisher?
(A) CCl4
(B) CO2
(C) O2
(D) 0
Answer :- (B) CO2

15. Necessary for combustion
(A) air
(B) water
(C) fire
(D) Flame.
Answer :- (A) Wind

16. What is the unit of calorific value of fuel?
(A) kg
(B) KJ/kg
(C) KJ
(D) K/J
Answer :- (B) KJ/kg

17. Which of the following is a combustible substance?

(A) glass
(B) Iron nail
(C) Cement
(D) Kerosene 
Answer :- (D) Kerosene

18. Which of the following conditions is necessary for the process of combustion?

(A) Presence of non-combustible substance
(B) Obtaining the combustion temperature of the substance
(C) Absence of air
(D) None of these.
Answer: (B) The combustion temperature of the substance is obtained.

19. Which of the following is an example of an explosion?
(A) Burning of wood
(B) Oil
(C) Burning of firecracker
(D) None of these
Answer :- (C) Burning of firecracker

20. Burning of wood is an example of which type of combustion?
(A) slow combustion
(B) Explosives
(C) Spontaneous combustion
(D) None of these.
Answer :- (A) slow combustion

21. Which of the following is the nourisher of burning?
(A) Hydrogen
(B) Carbon dioxide
(C) Nitrogen
(D) Oxygen
Answer :- (D) Oxygen

22. Which gas comes out of the fire extinguisher?
(A) Hydrogen
(B) Oxygen
(C) Nitrogen
(D) carbon dioxide
Answer :- (D) Carbon dioxide