Question

What will be the geometry and shape of $N{H}_2^{-}$?

• A. Trigonal planar, V - shape
• B. Tetrahedral, V - shape
• C. Tetrahedral, pyramidal - shape
• D. Trigonal bipyramidal, Trigonal - planar

Answer 1

The correct option is B Tetrahedral, V - shape

ep for $N{H}_2^{-}=\frac{(V+L+A-C)}{2}=\frac{(5+2+1)}{2}$ =4

(central atom $\to$ N, valence $\to$ 5)

4 ep $\Rightarrow$ Tetrahedral

Now,

ep = 4 & Ligands = 2 $\Rightarrow$ bp = 2 & lp = 2

Now, the geometry will be tetrahedral but there will be & lone pairs attached to it.

Because of lone pairs, the angle also decreases.

So, it will be having v - shape [Because while deciding shape. Lone pairs are not considered]