Question

Out of the following, how many compounds have tetrahedral geometry?
\text{NH}_4^+, \, \text{XeF}_4, \, [\text{NiCl}_4]^{2-}, \, [\text{PtCl}_4]^{2-}, \, [\text{Cu(NH}_3\text{)}_4]^{2+}, \, \text{BF}_3, \, [\text{Ni(CO)}_4]

Hint:

Tetrahedral geometry occurs when a central atom is surrounded by 4 substituents, leading to bond angles of 109.5°.

Answer 1

Correct Answer: 3

The compounds with tetrahedral geometry are: - \(\text{NH}_4^+\) (tetrahedral geometry due to 4 bonds on central atom), - \([ \text{Cu(NH}_3)_4]^{2+}\) (tetrahedral coordination), - \([ \text{Ni(CO)}_4] \) (tetrahedral geometry), - \(\text{XeF}_4\) (square planar geometry, so not tetrahedral), - \([ \text{NiCl}_4]^{2-}\) (tetrahedral geometry), - \([ \text{PtCl}_4]^{2-}\) (square planar geometry, so not tetrahedral), - \(\text{BF}_3\) (trigonal planar, so not tetrahedral).
Thus, 5 compounds have tetrahedral geometry.
Step 2: Conclusion.
The correct answer is (3) as 5 compounds have tetrahedral geometry.