Question

1. Write two points of difference
Vrite two points of difference between a chemical change and a physical chang
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Answer 1

Answer:  

Physical Change

1 Explanation of Physical Change:- In a physical change, the molecules are rearranged while their actual composition remains same.

Explanation of Chemical change:- In a chemical change, the molecular composition of a substance completely changes and a new substance is formed.

2 Example of Physical Change:- Some example of physical change are freezing of water, melting of wax, boiling of water, etc.

Examole of Chemical change:- A few examples of chemical change are digestion of food, burning of coal, rusting, etc.

3 Reversibility in Phisical Change:- Physical change is easily reversible i.e original substance can be recovered.

Reversibility in Chemical Change:- Chemical change is irreversible i.e. original substance cannot be recovered.

4 Formation of new substance:- In physical change, no new substance is formed.

A chemical change is always accompanied by one or more new substance(s).

5 Type of Change :- Physical change is a temporary change.

Chemical change is a permanent change.

6 Energy Production:- In a physical change, no energy is produced. In a chemical change, energy is produced (heat, light, sound, etc.)

7 Absorption of Energy:- Physical change involves very little to no absorption of energy.

During the chemical reaction, absorption and evolution of energy takes place.

8 Affects Physical change affects only physical properties i.e. shape, size, etc.

Chemical change both physical and chemical properties of the substance including its composition.