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JEE Main 2025 Jan 22 Shift 2, Chemistry Q16: Qualitative and Quantitative Analysis

JEE Main2025Jan 22, Shift 2Chemistry
Q.

Given below are two statement :

Statement (I) : Nitrogen, sulphur, halogen and phosphorus present in an organic compound are detected by Lassaigne's Test.

Statement (II) : The elements present in the compound are converted from covalent form into ionic form by fusing the compound with Magnesium in Lassaigne's test.

In the light of the above statements, choose the correct answer from the options given below :

  1. A

    Both Statement I and Statement II are true

  2. B

    Both Statement I and Statement II are false

  3. C

    Statement I is true but Statement II is false

  4. D

    Statement I is false but Statement II is true

Solution

Lassaigne's test is the classical qualitative method for detecting nitrogen, sulphur, halogens and phosphorus in organic compounds, so Statement-I is true.

The fusion in Lassaigne's test is performed with sodium metal (not magnesium). Sodium converts the covalently bound heteroatoms into ionic species such as , , , , which are then detected by suitable reagents. Statement-II is false because it names magnesium instead of sodium.

Statement I is true but Statement II is false.

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