Question

1. Give two examples of physical changes.
2. What happens when magnesium oxide is dissolved in water?
3. What type of change is burning of coal?
Short Answer Type-1 Questions:
1. What is meant by rusting of iron?
2. State any two conditions necessary for the rusting of iron.
3 Why is melting of ice to form water considered a physical change?
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Answer 1

Explanation:

1 : Boiling water, Crushing a can, melting an ice cube.

2 : Magnesium hydroxide will be formed.

3 : Chemical change

Short answer

1 : When an iron is kept in contact of air for a longer time. It is known as rusting of iron.

2 : Contact with air

Contact with water

3 : It is a physical change because the melting ice which become water can be changed again to ice that's why melting of ice into water is physical change

Answer 2

Ans1: melting of wax , stretching of rubber band
Ans2: magnesium hydroxide is formed
Ans3: The process by which one or more subtances having entirely different properties and composition from the original subtance is called chemical reaction