Which condition is not satisfied by an ideal solution?

Vapour pressure of chloroform (CHCl₃) and dichloromethane (CH₂Cl₂) at 25^oC are 200 mm Hg and 41.5 mm Hg respectively. Vapour pressure of the solution obtained by mixing 25.5 g of CHCl₃ and 40 g of CH₂Cl₂ at the same temperature will be
(Molecular mass of CHCl₃ = 119.5 u and molecular mass of CH₂Cl₂ = 85 u)

p_A and p_B are the vapour pressure of pure liquid components, A and B, respectively of an ideal binary solution. If x_A represents the mole fraction of component A, the total pressure of the solution will be

200 mL of an aqueous solution of a protein contains its 1.26 g. The osmotic pressure of this solution at 300 K is found to be 2.57 $$ \times $$ 10^$$-$$3 bar. The molar mass of protein will be (R = 0.083 L bar mol^$$-$$1 K^$$-$$1)