Question

The largest bond angle is in ______.

Options

• NH₃

• PH₃

• AsH₃

• BiH₃

Answer 1

The largest bond angle is in NH₃.

Explanation:

The bond angle in NH₃ is about 107.8° which is the largest among NH₃, PH₃, AsH₃, and BiH₃. This is because nitrogen is small and highly electronegative, causing greater repulsion between the lone pair and bond pairs of electrons. As we move down the group to heavier atoms like P, As, and Bi, the bond angle decreases due to the increasing size of the central atom and decreasing electronegativity, which reduces electron pair repulsion and hence lowers the bond angle (PH₃: 93.6°, AsH₃: 91.8°, BiH₃: 90°).