For an ideal binary liquid mixture ∆Smix>0 and ∆Gmix<0 For ideal solution; ∆Hmix=0 and ∆Vmix=0 ∆G = ∆H – T∆S ∆G should be –ve for reaction to be spontaneous, that is, ∆G < 0. When ∆G < 0, then ∆S should have value greater than zero