Question

Determine the electron-group arrangement, molecular shape, and ideal bond angle(s) for each of the following:

(a)${\mathbf{CO}}_3^{2-}$

(b)${\mathbf{SO}}_2$

(c)${\mathbf{CF}}_4$

Short answer

The shapes and bond angles of molecules can be determined from the VSEPR theory. The deviations arise mainly due to lone pair-lone pair repulsions.

Step-by-step solution

Step 1: CO32-CO32-

The structure of the molecule would be trigonal planar around the central atom carbon. Ideal bond angle would be${\mathbf{120}}^0$

Step 2: SO2

The sulphur atom is sp³hybridised. The expected structure of the molecule would be trigonal planar around the central atom sulphur. Ideal bond angle would be${\mathbf{120}}^0$.However, the lone pairs around the sulphur atom reduces the bond angle from ${\mathbf{120}}^0$. Then the shape can be considered bent.

Step 3: CF4

The shape of${\mathbf{CF}}_4$is tetrahedral. The expected bond angle is$\mathbf{109}\mathbf{.}{\mathbf{5}}^0$.