When a nonvolatile solute is added to a volatile solvent,the solution vapor pressure __________,the boiling point __________,the freezing point __________,and the osmotic pressure across a semipermeable membrane __________.
A)decreases,increases,decreases,decreases
B)increases,increases,decreases,increases
C)increases,decreases,increases,decreases
D)decreases,decreases,increases,decreases
E)decreases,increases,decreases,increases

Question

Quizplus · Accepted Answer

Adding a nonvolatile solute to a volatile solvent decreases the solution vapor pressure due to the solute particles occupying surface area and reducing the number of solvent molecules that can escape into the vapor phase. This leads to an increase in boiling point (colligative property) because a higher temperature is needed to make the vapor pressure equal to the external pressure. The freezing point decreases because the presence of solute particles disrupts the formation of a solid structure, requiring a lower temperature to freeze. The osmotic pressure increases because the solute creates a concentration gradient across a semipermeable membrane, causing solvent molecules to move into the solution to equalize the concentration, generating pressure.

When a Nonvolatile Solute Is Added to a Volatile Solvent,the