Q1: In case of a solution (not of a solid in a liquid), whose total volume is less than the sum of the volumes of its components in their pure states, solubility is

ANS:B - increases with rise in pressure.

In this scenario, where the total volume of the solution is less than the sum of the volumes of its components in their pure states, we are likely dealing with a non-ideal solution. This condition typically arises in systems where the components experience significant intermolecular interactions, such as in the case of liquid-liquid solutions. In such cases:

• Solubility is independent of temperature: Solubility typically depends on the nature of the solute and solvent, not on temperature, assuming that temperature changes don't significantly alter the nature of the intermolecular interactions.
• Solubility does not increase with the rise in pressure: Unlike gases, increasing pressure typically does not increase the solubility of a non-gaseous solute in a liquid solvent. So, it's unlikely that solubility increases with pressure in this scenario.
• Solubility does not necessarily increase with a decrease in pressure: Unlike gases, where decreasing pressure can cause gas molecules to escape from the solution, thereby decreasing solubility, the effect of pressure on the solubility of non-gaseous solutes in liquids is generally negligible.
• Solubility remains unchanged with pressure changes: This is the most reasonable assumption in this context. Changes in pressure are not expected to significantly affect the solubility of the solute in the solvent, especially when the solution behaves non-ideally.