Which of the following molecule is planar?

Options

A. `CH_4`
B. `NH_4`
C. `C_2H_4`
D. `SiCl_4`

Answer

C

Explanation

`H = 1/2 (4 + 2 - 0 + 0) = 3`
`rArr sp^2` hybridization
`rArr` Trigonal planar structure

So there are two triangular planar structures for each `H_2C`= group. Each .C. atom is `sp^2` hybridized and in the `C = C` bond there is axial overlapping of `sp^2 -sp^2 (sigma-"bond")` hybridized orbitals. So both the triangles will also be in one plane.