Four vessels of same volume consist equal masses of four gases $\mathrm{H}_2, \mathrm{Cl}_2, \mathrm{~N}_2$, and $\mathrm{O}_2$ separately at same temperature. The pressure exerted by the gas is maximum for

The solubility product of a sparingly soluble salt AX is $4.9 \times 10^{-13}$. What is its solubility in $\mathrm{mol} \mathrm{dm}^{-3}$ ?

Which from following cations develops lowest value of spin only magnetic moment?

How long should aqueous NaCl be electrolysed by passing 100 ampere current, so that 0.5 mol chlorine is released at anode?