Which of the following is NOT true of colligative properties? Colligative properties are...
A. responsible for lowering the vapor pressure of a solution versus the vapor pressure of the pure solvent.
B. dependent on the mass of solute present.
C. independent of the chemical identity of the solute.
D. dependent on the molar mass of the solute.
E. all of these are true.
Is the answer C? Please help and THANK YOU!
Yes C.
I tried C and it marked it wrong
Yes, you are correct! The answer is C. Colligative properties are independent of the chemical identity of the solute.
Now, let me explain how to arrive at this answer:
Colligative properties are characteristics of a solution that depend solely on the number of particles (such as molecules or ions) present in the solution, regardless of their chemical identity. These properties include freezing point depression, boiling point elevation, vapor pressure lowering, and osmotic pressure.
Option A states that colligative properties are responsible for lowering the vapor pressure of a solution compared to the vapor pressure of the pure solvent. This is true because adding a solute to a solvent decreases the number of solvent molecules at the surface, resulting in a lower vapor pressure.
Option B suggests that colligative properties are dependent on the mass of solute present. This is also true because a larger amount of solute means a greater number of solute particles present in the solution, giving rise to a greater impact on colligative properties.
Option D indicates that colligative properties are dependent on the molar mass of the solute. This is also true because the number of particles in a solution depends on the molar mass of the solute. Substances with higher molar masses will have a greater effect on colligative properties.
However, option C correctly states that colligative properties are independent of the chemical identity of the solute. This means that colligative properties will be the same regardless of whether the solute is a salt, sugar, or any other substance. Hence, option C is the correct answer.
I hope this explanation helps! Let me know if you have any further questions.