HARD
7th CBSE
IMPORTANT
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What is the chemical formula of rust?

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Important Questions on Physical and Chemical Changes

HARD
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q A
What is depositing a layer of zinc on iron called?
MEDIUM
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q A
What is the reaction in which a solid substance is obtained in its purest form?
MEDIUM
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q B
A reversible change is one in which the _____ substance can be recovered.
HARD
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q B
When carbon dioxide gas is passed through lime water, it turns _____.
HARD
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q B
Changes in which only _____ properties of a substance change are called physical changes.
MEDIUM
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q B
Changes in which new substances are formed are called _____ changes.
HARD
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q C
Classify the following change as physical or chemical:
Crumpled a sheet of aluminium foil
EASY
7th CBSE
IMPORTANT
Expanded Universal Science 7>Chapter 7 - Physical and Chemical Changes>ASSESSMENT ZONE>Q C
Classify the following changes as physical or chemical:
Melting ice cube.