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2 years ago

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Chemistry

1 answer:

Sever21 [200]2 years ago

7 0

<h3><u>Question:</u><u>-</u></h3>

Criteria for purity of organic solid is

(a) boiling point

(b) melting point

(d) none of these

<h3><u>Answer</u><u>:</u><u>-</u></h3>

(b) melting point

<h3><u>Explanation</u><u>:</u><u>-</u></h3>

Melting point is considered to be the best measure of purity of a substance.

When a purified sample is mixed with a small amount of pure compound , melting point of the mixture is determined.

If a substance is impure (contains impurities/other substance) the melting point of that substance will change.

________________________________

The purity percentage of a substance can be calculated by dividing the mass of the pure chemical by the total mass of the sample and multiplying this number by 100.

[Mass of pure chemical/total mass × 100]

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