Question

A solution contains 4.50 moles of water, 1.00 moles of sucrose (C12H22O11), and 1.10 moles of glucose. Sucrose and glucose are nonvolatile.Assuming an ideal mixture, what is the vapor pressure of this solution at 35°C, given that the vapor pressure of pure water at 35°C is 42.2 torr? _______ torr

Answer 1

`28.8\text{ torr}`

Step-by-step explanation:

Here, we want to get the vapor pressure of the solution

Firstly, we need to get the mole fraction of water

That would be the number of moles of water divided by the sum of the number of moles of all

We have that as:

`\frac{4.5}{1\text{ + 1.1 + 4.5 }}\text{ = 0.682}`

According to Raoult's law:

`\begin{gathered} Vapor\text{ pressure of solution = mole fraction of water }* \\ vapor\text{ pressure of pure water} \end{gathered}`

Thus, we have the vapor pressure of the solution as:

`0.682\text{ }*\text{ 42.2 = 28.8 torr}`