What is the vapor pressure of isopropanol (MW = 60.1) in a closed container of 70% isopropanol in water (MW = 18.0) at 25oC? Such a mixture contains 70 g of isopropanol and 30 g of water. The vapor pressure of pure isopropanol at 25oC = 50 torr

The vapor pressure of the 70% isopropanol solution is 21 Torr.

Explanation:

Relative lowering of vapor pressure for solution with non volatile solute is given by :

Where:

= Vapor pressure of pure solvent

p = Vapor pressure of solution

=  Mole fraction of solute

We have, 70% isopropanol solution which menas 70 grams of isopropanol (solvent) and 30 grams of water (solute).

Mass of water = 30 g

Moles of water =

Mass of isopropanol = 70 g

Moles of isopropanol =

Mole fraction of solute that is water :

Vapor pressure of the pure isopropanol =

Vapor pressure of the solution = p

Solving for p:

p = 20.57 Torr ≈ 21 Torr

The vapor pressure of the 70% isopropanol solution is 21 Torr.

answer: the rate of diffusion increases with increase in temperature.

increase in temperature, increases the molecular/particles speed (kinetic energy. diffusion means movement of particles through the material.

generally, the heavier the particle the more it interacts with the environment and more the temperature matters. so higher temperature results in higher diffusion.

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).