Q1: Out of two equilibrium curves, first one lies above the diagonal and the second lies below the diagonal in the x-y plot. It means that separation by distillation is

ANS:C - more readily done in the second case compared to first one.

Out of two equilibrium curves, where the first one lies above the diagonal and the second lies below the diagonal in the x-y plot, it means that separation by distillation is not possible in the second case unless vacuum is applied. In a distillation process, the separation of components is based on their relative volatility, which is determined by the position of their respective equilibrium curves on the x-y plot. When the equilibrium curve lies below the diagonal, it indicates that the more volatile component is in the liquid phase, making it difficult to separate by conventional distillation at atmospheric pressure. In such cases, applying vacuum lowers the boiling points of both components, shifting the equilibrium towards vaporization and facilitating separation. By reducing the pressure, the boiling point of the more volatile component can be lowered sufficiently to enable effective separation even when its equilibrium curve lies below the diagonal. Therefore, the correct statement is: not possible in the second case unless vacuum is applied.