JEE Main202623 January 2026Evening ShiftChemistryp Block Elements (Group 13 & 14)Actual
It is noticed that Pb ²⁺ is more stable than Pb ⁴⁺ but Sn ²⁺ is less stable than Sn ⁴⁺ . Observe the following reactions. PbO ₂+ Pb 2 PbO ; _ r G ^ (1) SnO ₂+ Sn 2 SnO ; _ r G ^ (2) Identify the correct set from the following
Options
- A_ r G ^ (1)<0 ; _ r G ^ (2)<0
- B_ r G ^ (1)>0 ; _ r G ^ (2)>0
- C_ r G ^ (1) 0
- D_ r G ^ (1)>0 ; _ r G ^ (2)<0
Correct answer
C. _ r G ^ (1) 0
Step-by-step solution
The stability of oxidation states in Group 14 is governed by the inert pair effect, which increases down the group. For Lead ( Pb ), the +2 oxidation state is more stable than the +4 state ( Pb²⁺ > Pb⁴⁺ ). In the reaction PbO₂ + Pb 2PbO , Pb⁴⁺ is being reduced to Pb²⁺ and Pb^0 is being oxidized to Pb²⁺ . Since the product contains the more stable oxidation state, the reaction is spontaneous, meaning _r G^ (1) For Tin ( Sn ), the +4 oxidation state is more stable than the +2 state ( Sn⁴⁺ > Sn²⁺ ). In the reaction Sn