Question

The most basic hydride of group 15 elements is

• A. NH$_3$
• B. PH$_3$
• C. SbH$_3$
• D. AsH$_3$

Hint:

When comparing basicity of hydrides in a group, the basicity decreases as the electronegativity of the central atom decreases.

Answer 1

The Correct Option is A

Step 1: Understanding the basicity of hydrides.
The basicity of a hydride depends on the ability of the central atom to donate electrons. As we move down group 15 elements, the electronegativity of the central atom decreases, which reduces its ability to donate electrons, making the hydride less basic.
Step 2: Analyzing the options.
(A) NH$_3$: This is the most basic hydride among the group 15 hydrides due to the high electronegativity of nitrogen and its ability to donate a lone pair of electrons.
(B) PH$_3$: Phosphine is less basic than ammonia, as phosphorus is less electronegative than nitrogen.
(C) SbH$_3$: Antimony hydride is even less basic due to the lower electronegativity of antimony compared to phosphorus and nitrogen.
(D) AsH$_3$: Arsine has a similar trend to SbH$_3$ in terms of basicity. It is less basic than ammonia.
Step 3: Conclusion.
The correct answer is (A) NH$_3$ as it is the most basic hydride in the group 15 family.