HARD
7th CBSE
IMPORTANT
Earn 100

Is magnesium hydroxide acidic or basic in nature? Why?

Important Questions on Physical and Chemical Changes

MEDIUM
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q C
Give examples where chemical changes are accompanied by change in smell.
EASY
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q D
Give two examples each of physical and chemical changes.
MEDIUM
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q D
What do you understand by ‘rust’? Represent the chemical change that occurs during rusting.
MEDIUM
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q D
What is stainless steel?
HARD
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q D
Define alloying.
MEDIUM
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q D
What is meant by crystallisation?
HARD
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q D
How does galvanising prevent rusting?
HARD
7th CBSE
IMPORTANT
Science Booster>Chapter 7 - Physical and Chemical Changes>PRACTICE TIME>Q E
Describe an activity to show the conditions necessary for rusting to take place.