EASY
8th Foundation
IMPORTANT
Earn 100

Read the given statements and select the correct option.

Statement 1: Kerosene oil and wood do not catch fire on their own at room temperature.

Statement 2: A combustible material cannot catch fire as long as its temperature is lower than its ignition temperature.

50% studentsanswered this correctly

Important Questions on Combustion and Flame

MEDIUM
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 7
In an experiment, 4.5 Kg of a fuel was completely burnt. The heat produced was 180,000 kJ. The calorific value of the fuel is:
EASY
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 8
What is the principle of soda fire extinguisher?
EASY
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 9
Which of the following reactions takes place in soda-acid type fire extinguisher?
MEDIUM
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 10

Match column I with column II and select the correct option from the given codes.

Column I Column II
P.  Rusting  (i)   Explosion
Q.  Burning of paper (ii)  Spontaneous combustion
R.  Sodium (iii)  Rapid combustion
S.  Fire crackers (iv)   Slow combustion

 

EASY
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 11
Which of the following represents the correct increasing order of calorific value of the given fuels?
EASY
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 12
Liquids and gaseous fuels have more advantages over solid fuels. Some advantages are:
(i) Calorific value of liquid and gaseous fuels is higher than solid fuels.
(ii) Liquids and gaseous fuels have higher ignition temperatures than solid fuels.
(iii) Liquids and gaseous fuels are easier to store since solid fuels occupy a lot of space.
(iv) Liquids and gaseous fuels burn completely, leaving no residue.
The correct advantages are:
EASY
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 13

A spoon is kept in contact with ice cubes for some time. Later, the same spoon was held over the flame of a small candle. The observation is shown in the figure. What do you infer from the given figure?

Question Image

 

EASY
8th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 8>Chapter 6 - Combustion and Flame>EXERCISES>Q 14
Which of the following statements are true?
I. Yellow flames are ideal for heating.
II. The substances which vaporise during burning give flames.
III. Luminous zone contains unburnt carbon particles.
IV. The non-luminous zone has the highest temperature.