Carbonic Acid and Carbonates

Q.

Hybridisation of carbon atom in $C{O}_3^{2-}$ is

1. $sp$

2. $s{p}^2$

3. $s{p}^3$

4. $\text{None of these}$

Q.

$C{O}_2+H_{2}O\rightleftharpoons$ ?

1. Cyanide

2. Cyanogen

3. Calcium Cyanamide

4. None of these

Q. Which of the following metal carbonates decompose on heating?

1. $N{a}_{2}C{O}_3$
2. $L{i}_{2}C{O}_3$
3. $K_{2}C{O}_3$
4. $MgC{O}_3$