NEET2002Chemistryp Block Elements (Group 13 & 14)Actual
Assertion : Stannous chloride gives grey precipitate with mercuric chloride, but stannic chloride does not do so. Reason : Stannous chloride is a powerful oxidising agent which oxidises mercuric chloride to metallic mercury.
Options
- AIf both the assertion and reason are true and reason is a correct explanation of the assertion.
- BIf both assertion and reason are true but assertion is not a correct explanation of the assertion.
- CIf the assertion is true but the reason is false.
- DIf both assertion and reason are false.
Correct answer
C. If the assertion is true but the reason is false.
Step-by-step solution
SnCl ₂ (stannous chloride) on reaction with mercuric chloride ( HgCl ₂ ) , oxidises to SnCl ₄ (stannic chloride ) SnCl ₂+2 HgCl ₂ SnCl ₄+ Hg ₂ Cl ₂ (Greyish) So in this reaction, stannous chloride is acting as reducing agent that reduces Hg (II) to Hg (I) and then to Hg (0) SnCl ₂+ Hg ₂ Cl ₂ 2 Hg + SnCl ₄