Which of the following statements are correct? A. Glycerol is purified by vacuum distillation because it decomposes at its normal boiling point. B. Aniline can be purified by steam distillation as aniline is miscible in water. C. Ethanol can be separated from ethanol water mixture by azeotropic distillation because it forms azeotrope. D. An organic compound is pure, if mixed M.P. is remained same. Choose the most appropriate answer from the options given below :

Practical Organic Chemistry PYQ — JEE Main 2024 · 6 Apr · Shift 1 · Q13 with Solution

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Correct answer: A

Check statement A:
Glycerol has a very high boiling point and tends to decompose at its normal boiling point. Therefore, it is purified by vacuum distillation so that it boils at a lower temperature.
Hence, A is correct.
Check statement B:
Steam distillation is used for substances that are immiscible or only slightly miscible in water and are volatile in steam.
Aniline is not miscible in water; it is only slightly soluble. So the given reason "as aniline is miscible in water" is wrong.
Hence, B is incorrect.
Check statement C:
Ethanol and water form an azeotrope (about $95.6\%$ ethanol). Such mixtures are separated/purified using azeotropic distillation.
Hence, C is correct.
Check statement D:
A common test of purity for solids is the mixed melting point test. If mixing the sample with a pure compound does not change the melting point, the compound is considered identical/pure.
Hence, D is correct.
Conclusion:
Correct statements are A, C, and D only.

Therefore, the correct option is A.