Which of the following statement(s) is/are true A. All physical changes are reversible B. All chemical changes are irreversible?

Only A
Only B
Both A and B
Neither A nor B

LohaHridoy

4 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 3 : Both A and B

Concept:

Every day a lot of changes occur in our surroundings.
Broadly, all the changes occurring around can be classified into 2 categories:
- Physical changes
- Chemical Changes

Explanation:

Physical change:

During a physical change, substances undergo a change in their physical properties, and the formation of no new substance takes place.
It is generally reversible because the physical changes can be reversed.
For example: melting of wax, freezing of water, etc.

Chemical change:

During a chemical change, the molecules of the reactants ( original substances) change to form molecules of the products that are substances that undergo chemical transformation to form new substances.
It is generally irreversible because the chemical changes can not be reversed.
For example: burning of fuels like LPG, petrol, etc, curdling of milk, rusting of iron, etc.

Thus, the correct answer is Both A and B.

4 views Answered 2022-09-04 04:29

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