Question

Explain why dissolving a nonvolatile solute in water affects the system in the following ways by selecting all true statements: (possible to have one or multiple answers)

1. The system has a higher boiling point than water.

[] The soulte lowers the vapor pressure of the water.

[] The solute increases the vapor pressure of the water.

[] A higher temperature is required to obtain a vapor pressure of water equal to 1 atm.

[] A lower temperature is required to obtain a vapor pressure of water equal to 1 atm.

[] The normal boiling point is the temperature at which teh vapor pressure is 1 atm.

2. The system has a lower freezing point than water.

[] Presence of the soulute lowers the triple point.

[] Presence of the solute increases the triple point.

[] For all substances, the change in the triple point results in a lower freezing point.

[] For water, the change in the triple point results in a lower freezing point.

[] None of these.

Answer 1

Q1. The system has a higher boiling point than water.

The true statements are

• The solute lowers the vapor pressure of the water.
• A higher temperature is required to obtain a vapor pressure of water equal to 1 atm.
• The normal boiling point is the temperature at which the vapor pressure is 1 atm.

Q2. The system has a lower freezing point than water.

The true statements are

• Presence of the solute lowers the triple point.
• For all substances, the change in the triple point results in a lower freezing point.
• For water, the change in the triple point results in a lower freezing point.