Question

the bond angle in co₃²⁻ is expected to be approximately
90 degrees
109.5 degrees
120 degrees
145 degrees
180 degrees

Explanation:

For $\text{CO}_3^{2-}$, the central C atom has 3 bonding pairs (to O atoms) and no lone pairs. This gives a trigonal planar electron geometry, where bond angles are approximately 120 degrees.

Answer:

120 degrees