Question

Which of the following solutions will show positive deviation from Raoult's law?

• A. Water and ethanol
• B. Acetone and $C{S}_2$
• C. Acetone and benzene
• D. All of the above

Answer 1

The correct option is D All of the above

If the attractive interaction of the solute - solvent particles are less than that of solute - solute and solvent - solvent interactions then the solutions shows positive deviation. The solution with positive deviation has the total pressure greater than the predicted value by Raoult's law. Here the extent of hydrogen bonding is interrupted in water and ethanol solution and for each of acetone and $C{S}_2$ and acetone and benzene solution, the dipolar interactions between solute-solvent molecules are weaker than the respective interactions among the solute-solute and solvent-solvent molecules. Thus, all of the solutions will show positive deviation from Raoult's law.