Identify the product in the following reaction:

Number of molecules/ions from the following in which the central atom is involved in $$\mathrm{sp}^3$$ hybridization is ________.

$$\mathrm{NO}_3^{-}, \mathrm{BCl}_3, \mathrm{ClO}_2^{-}, \mathrm{ClO}_3$$

The correct sequence of ligands in the order of decreasing field strength is :

The Molarity (M) of an aqueous solution containing $$5.85 \mathrm{~g}$$ of $$\mathrm{NaCl}$$ in $$500 \mathrm{~mL}$$ water is : (Given : Molar Mass $$\mathrm{Na}: 23$$ and $$\mathrm{Cl}: 35.5 \mathrm{~gmol}^{-1}$$)