List of top Chemistry Questions on Hybridisation

Order of size of $sp, sp^2$ and $sp^3$ orbitals is

The incorrect statement/s among the following is/are I. $ NCl_5 $ does not exist while $ PCl_5 $ does II. Lead prefers to form tetravalent compounds III. The three $ C-O $ bonds are not equal in the carbonate ion IV. Both $ O_2^+ $ and $ NO $ are paramagnetic