A binary solution of liquids A and B will show positive deviation from Raoult's law if it fulfills the following condition: 

A binary liquid (AB) shows positive deviation from Raoult’s law when ${\mathrm{P}}_{\mathrm{A}}>{\mathrm{P}}_{\mathrm{A}}^{\mathrm{o}}{\mathrm{X}}_{\mathrm{A}} \mathrm{and} {\mathrm{P}}_{\mathrm{B}}>{\mathrm{P}}_{\mathrm{B}}^{\mathrm{o}}{\mathrm{X}}_{\mathrm{B}}$ , Intermolecular forces $\text{A}-\text{A},\text{B}-\text{B}>\text{A}-\text{B}$, $△{\text{V}}_{\text{mix}}>0$ and  $△{\text{H}}_{\text{mix}}>0$.