ANS:C - >1

The relative volatility for the separation of a non-ideal binary mixture by distillation should typically be greater than 1. Relative volatility (𝛼α) is a measure of the difference in vapor pressures between the components of a binary mixture. It is defined as the ratio of the vapor pressure of the more volatile component to that of the less volatile component: 𝛼=𝑃vap, more volatile𝑃vap, less volatileα=Pvap, less volatile​Pvap, more volatile​​ In distillation, a higher relative volatility indicates that the more volatile component has a significantly higher vapor pressure compared to the less volatile component. This difference in vapor pressures facilitates the separation of the components by allowing the more volatile component to preferentially vaporize, while the less volatile component remains in the liquid phase. In general, for effective separation by distillation, the relative volatility should be greater than 1. A relative volatility of 1 indicates that the two components have similar vapor pressures and are difficult to separate by distillation. Therefore, the correct answer is greater than 1.