Calculate the molarity and mole fraction of a 2.35 m solution of acetone (CH3COCH3) dissolved in ethanol (C2H5OH). (Density of acetone = 0.788 g/cm3; density of ethanol = 0.789 g/cm3.) Assume that the final volume equals the sum of the volumes of acetone and ethanol.
2.35 m.
Take enough solution to have 2.35 moles. That mans you have 1 kg solvent (ethanol).
volume ethanol = m/d = 1000g/0.789 = ??.
2.35 mol acetone x molar mass acetone = grams acetone and mass/density = volume.
Add volume acetone to volume ethanol to find total volume.
Then 2.35 moles/L = M
For mole fraction.
moles acetone/total moles.
Check my work.
m doesn't stand for moles. it stands for molality. molality is moles of solute divided by kiligrams of solvent. that might be your problem.
To calculate the molarity and mole fraction of the solution, we need to determine the number of moles of acetone and ethanol.
Step 1: Calculate the volume of acetone and ethanol in liters.
The density of a substance can be used to convert mass to volume. We will use the given densities and the mass of each component to calculate their volumes.
Volume of acetone:
Density of acetone = 0.788 g/cm^3
Mass of acetone = Concentration of acetone × Volume of solution
= 2.35 mol/L × 1 L
= 2.35 mol
Volume of ethanol:
Density of ethanol = 0.789 g/cm^3
Mass of ethanol = (Concentration of acetone × Volume of solution) - Mass of acetone
= (2.35 mol/L × 1 L) - (2.35 mol)
= 0 mol
Step 2: Convert the volume from cm^3 to liters.
1 cm^3 = 0.001 L
Volume of acetone = 2.35 L
Volume of ethanol = 0 L
Step 3: Calculate the moles of acetone and ethanol.
Moles = Volume (L) × Molarity
Moles of acetone = 2.35 L × 2.35 mol/L
= 5.4975 mol
Moles of ethanol = 0 L × 0 mol/L
= 0 mol
Step 4: Calculate the total moles in the solution.
Total moles = Moles of acetone + Moles of ethanol
= 5.4975 mol
Step 5: Calculate the molarity of the solution.
Molarity = Total moles / Total volume of solution (in L)
= 5.4975 mol / 2.35 L
≈ 2.34 M
Step 6: Calculate the mole fraction of acetone.
Mole fraction = Moles of acetone / Total moles
= 5.4975 mol / 5.4975 mol
= 1.0
Therefore, the molarity of the solution is approximately 2.34 M, and the mole fraction of acetone is 1.0.
To calculate the molarity and mole fraction of the solution, we need to know the number of moles of acetone and ethanol present in the solution.
Step 1: Calculate the volume of acetone and ethanol.
Since the density of a substance is given in g/cm3, we need to convert it to grams per milliliter (g/mL) to be able to calculate the volume.
Density of acetone = 0.788 g/cm3
Density of ethanol = 0.789 g/cm3
We can assume that the final volume equals the sum of the volumes of acetone and ethanol. Let's denote the volume of acetone as V1 and the volume of ethanol as V2.
Given that the solution is 2.35 M (molar) and the final volume is the sum of the volumes of acetone and ethanol, we know that:
Molarity (M) = moles of solute / liters of solution
Step 2: Calculate moles of acetone and ethanol.
To determine the moles of acetone and ethanol, we'll be using the equation:
moles = mass / molar mass
The molar mass of acetone (CH3COCH3) is:
12.01 (C) + 1.01 (H) * 6 + 16.00 (O) = 58.08 g/mol
The molar mass of ethanol (C2H5OH) is:
12.01 (C) * 2 + 1.01 (H) * 6 + 16.00 (O) + 1.01(H) = 45.08 g/mol
Using the densities, we can calculate the mass of acetone and ethanol.
mass acetone = volume acetone * density acetone
mass ethanol = volume ethanol * density ethanol
Step 3: Calculate the molarity and mole fraction.
Molarity (M) = moles of solute / liters of solution
Moles of acetone / Ethanol = mass / molar mass
Finally, the mole fraction can be calculated using the formula:
Mole fraction (X) = moles of component / total moles of all components
Now, you can substitute the values into the formulas and calculate the molarity and mole fraction of the solution.