HARD
7th CBSE
IMPORTANT
Earn 100

An iron nail is taken to the moon. Another is kept near the Gateway of India, Mumbai, while the third one is kept near the Red Fort, Delhi. Compare the degree of rust formation on the three nails.

Important Questions on Physical and Chemical Changes

HARD
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q F
The liquefied petroleum gas (LPG) is the gas which is used for cooking at home. In the cylinder it comes as a liquid. When it comes out from the cylinder, it become a gas (Change A). Then it burns (Change B). What are the differences between change A and B?
HARD
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q F
The decomposition of animal waste by anaerobic bacteria produces biogas (Change A). The biogas is then burnt as fuel (Change B). What are the similarities between the two changes?