Class 8 Combustion And Flame CBSE Questions & Answers

Class 8 · Combustion And Flame

This is Science Class 8 Combustion and Flame CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
When a candle is lighted, the wick:
  • A
    absorbs liquid wax
    Correct
  • B
    none of the above are correct
  • C
    burns with yellow flame
  • D
    vapourizes
2
Rubbing of matchstick on sides of matchbox raises temperature to ignition temperature by producing:
  • A
    induction
  • B
    displacement
  • C
    conduction
  • D
    friction
    Correct
3
Read the following statements :i) Different substances have different ignition temperatures.ii) Matchstick tail has a low ignition point.
  • A
    statement i) is correct but ii) is wrong
    Correct
  • B
    both are wrong
  • C
    both are correct
  • D
    statement ii) is correct but i) is wrong
4
Read the following statements :i) High ignition temperature can cause fire hazards.ii) Low ignition temperature causes difficulty in ignition.
  • A
    both are correct
  • B
    statement ii) is correct but i) is wrong
  • C
    statement i) is correct but ii) is wrong
  • D
    both are wrong
    Correct
5
When a piece of rock from space enters earth
  • A
    induction
  • B
    friction
    Correct
  • C
    destruction
  • D
    internal reflection
6
Mohan was sitting in his drawing room watching television. Suddenly his television wires caught fire but to get rid off this fire he shoud not use :
  • A
    water
    Correct
  • B
    both water & soil
  • C
    soil
  • D
    sand
7
Respiration takes place in living organisms is an example of :
  • A
    slow combustion
    Correct
  • B
    rapid combustion
  • C
    spontaneous combustion
  • D
    incomplete combustion
8
Within a living cell, food is burned to produce energy through :
  • A
    respiration
    Correct
  • B
    combustion
  • C
    addition of Carbon dioxide and water
  • D
    gaseous exchange
9
Sunil wet a paper cup with water and then heated it over the flame :
  • A
    explosion occurs
  • B
    none of the above
  • C
    does not burn
    Correct
  • D
    burns immediately
10
Read the following statements :i) Matchstick burns on striking a smooth surface.ii) Striking generates enough heat to light the matchstick.
  • A
    statement ii) is correct but i) is wrong
    Correct
  • B
    both are wrong
  • C
    statement i) is correct but ii) is wrong
  • D
    both are correct
11
From the fire triangle, water removes:
  • A
    oxygen
  • B
    combustible substances
  • C
    both heat & oxygen
    Correct
  • D
    heat
12
Read the following statements :i) Carbon dioxide is inflammable gas.ii) Carbon dioxide is heavier than oxygen.
  • A
    both are wrong
  • B
    both are correct
  • C
    statement i) is correct but ii) is wrong
  • D
    statement ii) is correct but i) is wrong
    Correct
13
Find the odd one out:
  • A
    foam fire extinguisher
  • B
    carbon dioxide fire extinguisher
  • C
    oxygen fire extinguisher
    Correct
  • D
    soda acid fire extinguisher
14
A person after fire casualty is wrapped with blanket to :
  • A
    to cut the supply of carbon dioxide
  • B
    to cut oxygen supply
    Correct
  • C
    to increase the ignition temperature of body
  • D
    to cut the supply of combustible substance
15
Match the following :i) water…………..a) combustible substanceii) stone…………..b) hydrocarbons iii) fuel……………c) burns without flame iv) wood………….d) good conductor of electricity v) charcoal………e) non combustible substance
  • A
    i.c,ii.e,iii.d, iv.a, v.b
  • B
    i.b,ii.a,iii.d, iv.e, v.c
  • C
    i.b,ii.d,iii.e, iv.c, v.a
  • D
    i.d,ii.e,iii.b, iv.a, v.c
    Correct