Question

What is not a mixture ?
(I) Water
(2) Air
(3) Soil
(4) Chalk

Answer 1

Hello friend...
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Answer - option (4) Chalk.

Among these four options chalk is not a mixture. Chalk is chemically known as Calcium Carbonate as they are carbonates of calcium.

It's chemical formula is CaCO3.

It is used in wide range -

✓ in farming it is used to increase pH level of soil which has high acidic level.
✓ sometimes they are used for cleaning and polishing.
✓ It may also be used as antacid in small amount.
✓ it is also used for writing purpose on blackboard.
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Let's talk about other options -
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option (1) Water - Normal water contains dissolved gases, minerals etc.

option (2) Air - it is the mixture of various gases and dust particles as well.

option (3) Soil - It is the mixture of minerals, organic substances, inorganic substances, gases etc.
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Hope it will help you...
Best of luck...

Thanks !!!
Regards - Pratik Ratna