Question

Elements X and Y belong to Group 15. The difference between the electronegativity values of 'X' and phosphorus is higher than that of the difference between phosphorus and 'Y'. 'X' & 'Y' are respectively

• A. As & Bi
• B. Bi & N
• C. As & Sb
• D. N & As

Hint:

Electronegativity changes significantly between Period 2 and 3 elements, but less so down the rest of the group.

Answer 1

The Correct Option is D

To solve this question, we need to consider the electronegativity values of the elements in Group 15 of the Periodic Table, which includes Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb), and Bismuth (Bi).

1. The electronegativity generally decreases down the group in the periodic table. The approximate electronegativity values are:
   • Nitrogen (N): 3.0
   • Phosphorus (P): 2.1
   • Arsenic (As): 2.0
   • Antimony (Sb): 1.9
   • Bismuth (Bi): 1.9
2. The problem states that the difference between the electronegativity values of 'X' and phosphorus is higher than that between phosphorus and 'Y'. Let's calculate these differences:
   • The difference between N and P: 3.0 - 2.1 = 0.9
   • The difference between As and P: 2.0 - 2.1 = -0.1
   • The difference between Sb and P: 1.9 - 2.1 = -0.2
   • The difference between Bi and P: 1.9 - 2.1 = -0.2
3. We need 'X' to have a difference from P that is greater than the difference between P and 'Y'. Therefore, 'X' should be more electronegative than P, which strongly suggests 'X' is N, and among the options provided, N & As fits correctly.
4. Options Analysis:
   • As & Bi: Both have lower electronegativity than P, ruling this out.
   • Bi & N: Bi has lower electronegativity than P, ruling this out as potential 'X'.
   • As & Sb: Both have electronegativity similar or lower than P.
   • N & As: N is more electronegative than P, and As is less, fitting the condition given in the question.

Therefore, the correct choice is N & As.