MEDIUM
8th CBSE
IMPORTANT
Earn 100

What are the products obtained on refining petroleum? Write their main uses.

Important Questions on Combustion and Fossil Fuels

MEDIUM
8th CBSE
IMPORTANT
Name any four air pollutants and describe their harmful effects.
HARD
8th CBSE
IMPORTANT

Recall and complete the concept map given below.

Question Image

MEDIUM
8th CBSE
IMPORTANT
Why is hydrogen not used as a domestic fuel even though it has the highest calorific value?
HARD
8th CBSE
IMPORTANT
Mitali and John purchased gas stoves from a shop both of which were of the same type. After a month of use, they found that Mitali’s stove produces a yellow flame, while John’s stove produces a blue one. Who needs to clean the burner of the stove? Why?
MEDIUM
8th CBSE
IMPORTANT
Are fossil fuels a boon or a curse? Discuss.
MEDIUM
8th CBSE
IMPORTANT
Look at the picture given below. It shows different colours of the flame with change in oxygen supply. Number them in correct order from 1 to 4 according to increase in oxygen supply.
C:\Users\pk\Desktop\Colour of flame.PNG