Question

A solution contains 50.0 g of heptane (C7H16) and 50.0g of octane (C8H20) at 25oC. The vapor pressures of pure heptane and pure octane at this temperature are 45.8 and 10.9 Torr, respectively.

Assuming ideal behavior, calculate the:

1) vapor pressure of each of the solution components in the mixture

2) total pressure above the solution

3) composition of the vapor in mass percent

Please explain! Thank you.

Answer #1

Answer: According to the question : You can calculate the total vapor pressure of the solution by multiplying the vapor pressure of each component by its mole fraction in the mixture, and then adding those together.

mole fraction of heptane = moles heptane / (moles heptane + moles octane)

moles of heptane = 50 / 100.21 = 0.49

moles of octane = 50/114.23 = 0.44

mole fraction of heptane = 0.49 / 0.49+ 0.44 = 0.526

Mole fraction of octane = 0.44 / 0.44+ 0.49 = 0.474

Now, we have to use Pa = Xa * Ptotal

Ptotal = Pa/Xa = 45.8/0.526 = 87.07 atm

For Octane = 10.9 / 0.474 = 22.995 atm

And the total pressure is = P1 + P2 = 87.07 + 22.995 = 110.065 atm

Hence it is all about the given question Thank you :)

A solution contains 49.0 g of heptane (C7H16)and 59.0 g of
octane (C8H18) at 25 ∘C. The vapor pressures of pure heptane and
pure octane at 25 ∘C are 45.8 torr and 10.9 torr, respectively.
Assuming ideal behavior, calculate each of the following. (Note
that the mole fraction of an individual gas component in an ideal
gas mixture can be expressed in terms of the component's partial
pressure.)
A) The vapor pressure of heptane in the mixture
B) The Vapor...

A solution of benzene (C6H6) and toluene (C7H8) is 27.0 %
benzene by mass. The vapor pressures of pure benzene and pure
toluene at 25 ∘C are 94.2 torr and 28.4 torr, respectively.
Assuming ideal behavior, calculate the following.
Calculate A) The vapor pressure of each of the solution
components in the mixture. B) The composition of the vapor in mass
percent.

Calculate the vapor pressure of a solution prepared by
dissolving 13g of n-heptane (C7H16) in 87g of
n-octane (C8H18) at 25oC). [NOTE:
both heptane and octane and volatile, hence both will exert a vapor
pressure when using Raoult's Law]

A solution of benzene (C6H6) and toluene (C7H8) is 25.0 %
benzene by mass. The vapor pressures of pure benzene and pure
toluene at 25∘C are 94.2 and 28.4 torr, respectively.
A)Assuming ideal behavior, calculate the vapor pressure of
benzene in the mixture.
B)Assuming ideal behavior, calculate the vapor pressure of
toluene in the mixture.

Please show all work. Thanks!
Consider a solution with xA = 0.220 at 30?C in equilibrium with
the vapor. The vapor pressures of the pure components at this
temperature are: p? A = 73.0kPa and p? B = 92.1kPa.
(a) Predict the vapor pressure and its composition at these
conditions assuming ideal solution.
(b) Experimentally it was found that the actual vapor pressure
was 1.00atm and yA = 0.314. Calculate the activities and activity
coe?cients of both components in this...

100.0 g of benzene is mixed with 100.0 g of toluene to form a
solution that can be considered ideal. What is the total vapor
pressure (in Torr) of this solution at 293 K? The molar masses of
benzene and toluene are 78.11 g/mol and 92.14 g/mol respectively.
At 293 K the vapor pressures of pure benzene and pure toluene are
74.7 Torr and 22.3 Torr respectively. Report your result with 1
decimal place.

A solution that contains nitromethane (1) in acetonitrile (2) is
heated at a constant pressure of 1 bar until the first bubble
appears. If the temperature of the solution at this point is
85◦C, what is the composition of the original
solution?
You may assume that the solution is ideal. The saturation
pressures for the pure components (in kPa) for T in
◦C are given by
ln(p1sat) = 14.2742 –
2945.47/(224 + T)
ln(p2sat) = 14.2043 –
2972.64/(209 + T)

A solution contains equal amounts (in moles) of liquid
components A and B. The vapor pressure of pure A is 100 mmHg and
that of pure B is 200 mmHg.
What is the vapor pressure above the solution assuming it is an
ideal solution?
The experimentally measured vapor pressure is 150 mmHg. What
does this indicate about relative strengths of the interactions
between solute and solvent molecules?
Please help me

We have a mixture, which is an ideal solution in the liquid
phase and an ideal-gas mixture in the vapor phase, of n-heptane (1)
and n-octane (2) at a pressure of 1 bar with z1 = 0.25.
(a) What are the bubble and dew temperatures?
(b) Calculate the heat required to bring the solution from its
bubble temperature to its dew temperature. Please use the Antoine
equations given in P11.5 to find the saturation pressures of these
species.
lnPsat= A-B/(C+t)...

As solute is dissolved in a solvent, the vapor pressure of the
solution changes according to Raoult's law
Psoln=Psolv×Xsolv
where Psoln is the vapor pressure of the solution,
Psolv is the vapor pressure of the pure solvent, and
Xsolv is the mole fraction of the solvent. If the solute
dissociates into ions, the term Xsolv must be modified to
take into consideration the total number of moles of particles in
the solution, both ions and molecules. When a solution contains...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 3 minutes ago

asked 11 minutes ago

asked 11 minutes ago

asked 13 minutes ago

asked 19 minutes ago

asked 23 minutes ago

asked 29 minutes ago

asked 37 minutes ago

asked 39 minutes ago

asked 42 minutes ago

asked 47 minutes ago

asked 49 minutes ago