JEE MainChemistryp Block Elements (Group 15, 16, 17 & 18)
Consider the following statements regarding the properties of Group 15 elements: (A) Nitrogen has a lower tendency for catenation than phosphorus because the N-N single bond is weaker than the P-P single bond. (B) The tendency to undergo disproportionation in the +3 oxidation state decreases from phosphorus to bismuth. (C) All Group 15 elements readily disproportionate in their +3 oxidation state in aqueous solution.
Options
- A(A) and (B) only
- B(A), (B) and (C) only
- C(A) and (D) only
- D(C) and (D) only
Correct answer
A. (A) and (B) only
Step-by-step solution
Statement (A) is correct. The catenation tendency depends on the strength of the element-element single bond. Since the N-N single bond is weaker than the P-P single bond (due to high lone pair-lone pair repulsion in the smaller nitrogen atoms), nitrogen shows a much lower tendency for catenation than phosphorus. Statement (B) is correct. Moving down the group from P to Bi, the stability of the +3 oxidation state increases due to the inert pair effect. Consequently, the tendency of the +3 state to disproportionate