The number of molecules from the following which contain only two lone pair of electrons is ________

$$\mathrm{H}_{2} \mathrm{O}, \mathrm{N}_{2}, \mathrm{CO}, \mathrm{XeF}_{4}, \mathrm{NH}_{3}, \mathrm{NO}, \mathrm{CO}_{2}, \mathrm{~F}_{2}$$

For a metal ion, the calculated magnetic moment is $$4.90 ~\mathrm{BM}$$. This metal ion has ___________ number of unpaired electrons.

In alkaline medium, the reduction of permanganate anion involves a gain of __________ electrons.

The number of incorrect statement/s from the following is ___________

A. The successive half lives of zero order reactions decreases with time.

B. A substance appearing as reactant in the chemical equation may not affect the rate of reaction

C. Order and molecularity of a chemical reaction can be a fractional number

D. The rate constant units of zero and second order reaction are $$\mathrm{mol} ~\mathrm{L}^{-1} \mathrm{~s}^{-1}$$ and $$\mathrm{mol}^{-1} \mathrm{~L} \mathrm{~s}^{-1}$$ respectively