NEET2026Chemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Given below are two statements: Statement-I : Heating NaCl with concentrated H₂ SO₄ and MnO₂ results in oxidation of Mn. Statement-II : Heating NaI with concentrated H₂ SO₄ and MnO₂ results in reduction of Mn. In light of the above statements, choose the most appropriate answer from the options given below:
Options
- AStatement-I is incorrect but Statement-II is correct.
- BBoth Statement-I and Statement-II are correct.
- CBoth Statement-I and Statement-II are incorrect.
- DStatement-I is correct but Statement-II is incorrect.
Correct answer
A. Statement-I is incorrect but Statement-II is correct.
Step-by-step solution
The reaction of NaCl with concentrated H ₂ SO ₄ and MnO ₂ is given by: 2 NaCl + MnO ₂ + 2 H ₂ SO ₄ Na ₂ SO ₄ + MnSO ₄ + 2 H ₂ O + Cl ₂ In this reaction, the oxidation state of Mn changes from +4 in MnO ₂ to +2 in MnSO ₄ . Since the oxidation state decreases, Mn undergoes reduction, not oxidation. Thus, Statement-I is incorrect. The reaction of NaI with concentrated H ₂ SO ₄ and MnO ₂ is given by: 2 NaI + MnO ₂ + 2 H ₂ SO ₄ Na ₂ SO ₄ + MnSO ₄ + 2 H ₂ O + I ₂ Here, the oxidation state of Mn also changes from +4 to +2