Acetone, C3H6O, and ethyl acetate, C4H8O2, are organic liquids often used as solvents. At 30 degrees C, the vapor pressure of acetone is 285 mm Hg and the vapor pressure of ethyl acetate is 118mm Hg. the solution is prepared at 30 degrees C by dissolving 27.0 g of acetone in 22.5 g of ethyl acetate.

A. What is the mole fraction of each component in the liquid mixture?

B. What is the mole fraction of each comment in the vapor at 30 degrees C?

How do I even START this problem? I am so confused.

Calculate moles acetone.

Calculate moles ethyl acetate.
Add mole acetone to moles ethyl acetate for total moles.
Now you are set up.
A. liquid
mole fraction acetone = moles acetone/total moles.
mole fraction ethyl acetate = moles ethyl acetate/total moles.

Part B. vapor
vapor (partial) pressure acetone = mole fraction acetone x normal vapor pressure acetone.

vapor (partial) pressure ethyl acetate = mole fraction ethyl acetate x normal vp ethyl acetate.

add partial pressure acetone in vapor to partial pressure ethyl acetate in vapor to obtain total pressure.
Then
mole fraction acetone = partial pressure acetone/total pressure
mole fraction ethyl acetate = partial pressure ethyl acetate/total pressure.

Check my thinking.

When I did that I got this:

2.6 for acetone mole fraction
1.4 for ethyl acetate mole fraction

119 acetate vapor
30 ethyl acetate vapor

None of those answers were correct. :[

To solve this problem, you can follow these steps:

Step 1: Find the number of moles for each component:
- Determine the molar mass of acetone (C3H6O): 12.01 g/mol (C) + 1.01 g/mol (H) + 16.00 g/mol (O) = 58.08 g/mol
- Calculate the number of moles of acetone: 27.0 g / 58.08 g/mol = 0.465 mol

- Determine the molar mass of ethyl acetate (C4H8O2): 12.01 g/mol (C) + 1.01 g/mol (H) + 16.00 g/mol (O) = 88.11 g/mol
- Calculate the number of moles of ethyl acetate: 22.5 g / 88.11 g/mol = 0.255 mol

Step 2: Calculate the total moles in the mixture:
- Total moles = moles of acetone + moles of ethyl acetate = 0.465 mol + 0.255 mol = 0.720 mol

Step 3: Calculate the mole fraction of each component in the liquid mixture:
- Mole fraction of acetone = moles of acetone / total moles = 0.465 mol / 0.720 mol = 0.645
- Mole fraction of ethyl acetate = moles of ethyl acetate / total moles = 0.255 mol / 0.720 mol = 0.355

Step 4: Calculate the vapor pressure of each component in the vapor:
- For acetone, the mole fraction in the vapor is equal to the mole fraction in the liquid mixture (0.645).
- For ethyl acetate, the mole fraction in the vapor is equal to the mole fraction in the liquid mixture (0.355).

So, the mole fraction of each component both in the liquid mixture and in the vapor at 30 degrees C is:
A. Mole fraction of acetone in the liquid mixture = 0.645
Mole fraction of ethyl acetate in the liquid mixture = 0.355

B. Mole fraction of acetone in the vapor at 30 degrees C = 0.645
Mole fraction of ethyl acetate in the vapor at 30 degrees C = 0.355

To begin solving this problem, we can first calculate the number of moles of each component in the liquid mixture.

To do this, we need to convert the masses given (27.0 g for acetone and 22.5 g for ethyl acetate) into moles using their respective molar masses.

The molar mass of acetone (C3H6O) is calculated as follows:
Molar mass = (3 * atomic mass of carbon) + (6 * atomic mass of hydrogen) + (1 * atomic mass of oxygen)

By referring to the periodic table, the atomic weights are:
Carbon (C) = 12.01 g/mol
Hydrogen (H) = 1.01 g/mol
Oxygen (O) = 16.00 g/mol

Plugging in the values:
Molar mass of acetone = (3 * 12.01) + (6 * 1.01) + (1 * 16.00) = 58.08 g/mol

Similarly, we can calculate the molar mass of ethyl acetate (C4H8O2):
Molar mass of ethyl acetate = (4 * 12.01) + (8 * 1.01) + (2 * 16.00) = 88.11 g/mol

Next, we can use the formula Moles = Mass / Molar mass to find the moles of each component:
Moles of acetone = 27.0 g / 58.08 g/mol
Moles of ethyl acetate = 22.5 g / 88.11 g/mol

Now that we know the number of moles of each component, we can move on to calculating the mole fraction.

A. Mole fraction of each component in the liquid mixture:
The mole fraction of a component is calculated by dividing the moles of the component by the total moles of all components.

Mole fraction of acetone = moles of acetone / (moles of acetone + moles of ethyl acetate)
Mole fraction of ethyl acetate = moles of ethyl acetate / (moles of acetone + moles of ethyl acetate)

B. Mole fraction of each component in the vapor at 30 degrees C:
To determine the mole fraction of each component in the vapor, we need to consider their vapor pressures.

The ratio of vapor pressure to total vapor pressure is equal to the mole fraction of that component in the vapor phase.

Mole fraction of acetone in vapor = (vapor pressure of acetone) / (vapor pressure of acetone + vapor pressure of ethyl acetate)
Mole fraction of ethyl acetate in vapor = (vapor pressure of ethyl acetate) / (vapor pressure of acetone + vapor pressure of ethyl acetate)

By substituting the given vapor pressures of acetone and ethyl acetate at 30 degrees C, you can evaluate both mole fractions.

Note: The values for vapor pressure can be typically found in chemical data references or experimentally determined using suitable equipment.