How do I do this problem
Assume you dissolve 2.56 g of malic acid, C4H6O5, in half a liter of water (500.0 g).
Calculate the molarity, molality, mole fraction, and weight percent of acid in the
solution. (Assume the final volume of the solution is 500. mL)
To solve this problem, you need to calculate the molarity, molality, mole fraction, and weight percent of the acid solution. Let's go step by step:
1. Calculate the molarity:
Molarity (M) is the number of moles of solute (in this case, malic acid) divided by the volume of the solution in liters. We can use the equation:
M = moles of solute / volume of solution (in liters)
First, you need to calculate the number of moles of malic acid:
Moles = mass / molar mass
The molar mass of malic acid (C4H6O5) can be calculated as follows:
(4 × atomic mass of carbon) + (6 × atomic mass of hydrogen) + (5 × atomic mass of oxygen)
Next, divide the mass of malic acid (2.56 g) by its molar mass to calculate the number of moles.
2. Calculate the molality:
Molality (m) is the number of moles of solute divided by the mass of the solvent (in this case, water) in kilograms. The equation for molality is:
m = moles of solute / mass of solvent (in kg)
To calculate the molality, divide the number of moles of malic acid by the mass of water (500.0 g) and convert the mass to kg.
3. Calculate the mole fraction:
The mole fraction (χ) is the ratio of the number of moles of a component (in this case, malic acid) to the total number of moles in the solution. The equation for the mole fraction is:
χ = moles of solute / total moles in the solution
First, you need to determine the moles of water by dividing its mass (500.0 g) by its molar mass. Then sum up the number of moles of malic acid and water to find the total moles in the solution. Finally, calculate the mole fraction of malic acid by dividing its moles by the total moles in the solution.
4. Calculate the weight percent:
Weight percent is the weight of the solute (in this case, malic acid) divided by the total weight of the solution, multiplied by 100%. The formula for weight percent is:
Weight percent = (mass of solute / total mass of solution) × 100%
To calculate the weight percent, divide the mass of malic acid by the total mass of the solution (malic acid + water) and multiply by 100%.
Once you have the necessary values, you can calculate the molarity, molality, mole fraction, and weight percent of the malic acid solution.