Chemistry - Liquid Solution Question with Solution | TestHub

One molar$\text{(1}\text{M)}$aqueous solution is more concentrated than one molal aqueous solution of the same solute. In solution,${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$provides three ions. While$\text{NaCl}$provides two ions. Hence, vapour pressure of solution of$\text{NaCl}$is higher (as it gives less ions). Therefore,$\text{1}\text{molal}\text{NaCl}$will have the maximum vapour pressure.