1-propanol (P1° = 20.9 Torr at 25 °C) and 2-propanol (P2° = 45.2 Torr at 25 °C) form ideal solutions in all proportions. Let x1 and x2 represent the mole fractions of 1-propanol and 2-propanol in a liquid mixture, respectively, and y1 and y2 represent the mole fractions of each in the vapor phase. For a solution of these liquids with x1 = 0.200, calculate the composition of the vapor phase at 25 °C.

y1=? Y2=?

Can you do P1soln = X1*P1

P2soln = X2*P2
Total pressure of soln = P1soln + P2soln.

Then composition.
y1 = P1soln/total P
y2 = P2soln/total P

Why did the vapor phase go to therapy?

Because it was feeling a little mixed up!

But don't worry, I've got your back! To calculate the composition of the vapor phase, we can use Raoult's law. According to Raoult's law, the partial pressure of a component in the vapor phase is equal to the mole fraction of that component in the liquid mixture, multiplied by its vapor pressure at that temperature.

So, let's calculate!

For 1-propanol:
y1 = x1 * P1°
= 0.200 * 20.9 Torr

For 2-propanol:
y2 = x2 * P2°
= (1 - x1) * P2°
= (1 - 0.200) * 45.2 Torr

Now you can plug in the values and do the calculations. Have fun!

To determine the composition of the vapor phase, we can use Raoult's Law, which states that the partial pressure of a component in a solution is equal to the vapor pressure of the component multiplied by its mole fraction in the solution.

For component 1-propanol (1), the partial pressure in the vapor phase (P1) is given by:

P1 = P1° * y1

For component 2-propanol (2), the partial pressure in the vapor phase (P2) is given by:

P2 = P2° * y2

Since the sum of mole fractions in a binary solution is 1, we have:

x1 + x2 = 1

Given that x1 = 0.200, we can solve for x2:

x2 = 1 - x1
= 1 - 0.200
= 0.800

Now, to find y1 and y2, we need to use the equation for total pressure in the system. At equilibrium, the sum of the partial pressures is equal to the total pressure:

P_total = P1 + P2

Substituting the expressions for P1 and P2:

P_total = P1° * y1 + P2° * y2

Since the vapor phase composition is obtained when the solution is at equilibrium, we can assume that the total pressure is equal to the vapor pressure of the pure components:

P_total = P1° + P2°

Given that P1° = 20.9 Torr and P2° = 45.2 Torr, we can substitute these values into the equation for P_total:

P_total = 20.9 Torr + 45.2 Torr
= 66.1 Torr

Now we can solve for y1 and y2 using the equations:

y1 = P1 / P_total
y2 = P2 / P_total

Substituting the given values:

y1 = (P1° * y1) / P_total
y2 = (P2° * y2) / P_total

Simplifying, we have:

y1 = (P1° * y1) / (P1° + P2°)
y2 = (P2° * y2) / (P1° + P2°)

Substituting the known values:

y1 = (20.9 Torr * y1) / (20.9 Torr + 45.2 Torr)
y2 = (45.2 Torr * y2) / (20.9 Torr + 45.2 Torr)

To solve for y1 and y2, we can plug these equations into a system of simultaneous equations and solve for them using mathematical methods such as substitution or elimination.

Unfortunately, without additional information or values for y1 or y2, we cannot provide the specific compositions of the vapor phase at 25 °C for this solution.

To calculate the composition of the vapor phase, we will use Raoult's Law, which states that the vapor pressure of a component in an ideal solution is equal to the mole fraction of that component multiplied by its pure vapor pressure.

Given:
P1° = 20.9 Torr (vapor pressure of 1-propanol)
P2° = 45.2 Torr (vapor pressure of 2-propanol)
x1 = 0.200 (mole fraction of 1-propanol)

First, we need to calculate the mole fraction of 2-propanol (x2) using the formula:

x1 + x2 = 1
0.200 + x2 = 1
x2 = 1 - 0.200
x2 = 0.800

Next, we can calculate the mole fraction of 1-propanol in the vapor phase (y1) using Raoult's Law:

y1 = x1 * P1°
y1 = 0.200 * 20.9 Torr
y1 = 4.18 Torr

Similarly, we can calculate the mole fraction of 2-propanol in the vapor phase (y2):

y2 = x2 * P2°
y2 = 0.800 * 45.2 Torr
y2 = 36.16 Torr

Therefore, at 25 °C, the composition of the vapor phase is:
y1 = 4.18 Torr
y2 = 36.16 Torr