Two liquids A and B form an ideal solution.The solution has a vapour pressure of 7000 torr at 80^@C.It is distilled til 2//3^(rd) of the solution is collected as contensate. The composition of the condensate is x'_A=0.75 and that of the residue is x''_A=0.30.If the vapour pressure of the residue at 80^@C is 600 Torr, which of the following is/are true ?

Two liquids A and B form an ideal solution.The solution has a vapour p

1.	Two liquids A and B form an ideal solution.The solution has a vapour pressure of 7000 torr at 80^@C.It is distilled til 2//3^(rd) of the solution is collected as contensate. The composition of the condensate is x'_A=0.75 and that of the residue is x''_A=0.30.If the vapour pressure of the residue at 80^@C is 600 Torr, which of the following is/are true ?
Answer» The COMPOSITION of the original liquid was `x_A=0.6` The composition of the original liquid was `x_A=0.4` `P_A^C=2500/3` Torr `P_B^C=500` Torr Solution :`X_AP_A^@+X_BP_B^@=700`..(i) `X_A''P_A^@+X_B''P_B^@=0.30P_A^@+0.70 P_B^@=600`..(ii) if moles of A & B initially are x & y then `x=0.75xx2/3(x+y)+0.30xx1/3(x+y)`..(III) & `x_A=x/(x+y)` or `x_B=y/(x+y)`..(IV) Solving gives `X_A=0.6, " " , X_B=0.4, " " P_A^@=2500/3 "torr" & " " P_B^@=500` torr