\({P_T}\, = {\chi _A}P_A^o + {\chi _B}P_B^o\, = 0.4\, \times \,7\, \times \,{10^3}\, + \,0.6\, \times \,12\, \times \,{10^3}\, = \,{10^4}\)
\(0.4\, \times \,7\, \times \,{10^3}\, = \,{Y_A}\, \times \,{10^4}\)
\({Y_A}\, = \,0.28\)
\({Y_B}\, = \,1 - 0.28\, = 0.72\)
$(R =0.083\, L\, bar \,K ^{-1} \,mol ^{-1})$ (નજીકનો પૂર્ણાંક)