A solution is made by dissolving 55g of KCl in enough water to make 1.00 L of solution. Assume that the density of the solution is 1.00 g/mol. Calculate the mass percent, molarity, molality, and mole fraction of KCl.
To calculate the mass percent, molarity, molality, and mole fraction of KCl in the solution, follow these steps:
1. Calculate the mass percent of KCl:
Mass percent = (mass of solute / mass of solution) x 100
In this case, the mass of solute is 55g of KCl, and the mass of solution is the density of the solution (1.00 g/mL) multiplied by the volume of the solution (1.00 L):
Mass of solution = Density x Volume = 1.00 g/mL x 1000 mL = 1000 g
Now we can calculate the mass percent of KCl:
Mass percent = (55g / 1000g) x 100 = 5.5%
2. Calculate the molarity of KCl:
Molarity = moles of solute / volume of solution in liters
First, we need to calculate the moles of KCl. The molar mass of KCl is the sum of the atomic masses of potassium (39.10 g/mol) and chlorine (35.45 g/mol):
Molar mass of KCl = 39.10 g/mol + 35.45 g/mol = 74.55 g/mol
Now we can calculate the moles of KCl:
Moles of KCl = mass of KCl / molar mass of KCl
Moles of KCl = 55g / 74.55 g/mol = 0.737 moles
Finally, we can calculate the molarity of KCl:
Molarity = 0.737 moles / 1.00 L = 0.737 M
3. Calculate the molality of KCl:
Molality = moles of solute / mass of solvent in kg
In this case, the mass of solvent is the mass of solution minus the mass of solute:
Mass of solvent = Mass of solution - Mass of solute
Mass of solvent = 1000 g - 55 g = 945 g
Now we can calculate the molality of KCl:
Molality = 0.737 moles / 0.945 kg = 0.778 mol/kg
4. Calculate the mole fraction of KCl:
Mole fraction = moles of solute / total moles of all components
In this case, there is only one component (KCl) in the solution, so the total moles of all components is equal to the moles of KCl:
Mole fraction of KCl = 0.737 moles / 0.737 moles = 1.000
Therefore, the mass percent of KCl is 5.5%, the molarity is 0.737 M, the molality is 0.778 mol/kg, and the mole fraction is 1.000.
To calculate the mass percent, molarity, molality, and mole fraction of KCl in the solution, you need to use the given information.
Step 1: Calculate the mass percent of KCl.
Mass percent = (mass of solute / mass of solution) x 100
Mass of KCl = 55g
Mass of solution = 55g (given) + 1000g (density) = 1055g
Mass percent = (55g / 1055g) x 100 = 5.22%
Step 2: Calculate the molarity of KCl.
Molarity = (moles of solute / volume of solution in liters)
First, we need to calculate the moles of KCl.
Moles of KCl = mass of KCl / molar mass of KCl
Molar mass of KCl = 39.10 g/mol (atomic mass of potassium) + 35.45 g/mol (atomic mass of chlorine) = 74.55 g/mol
Moles of KCl = 55g / 74.55 g/mol = 0.738 mol
Now, we can calculate the molarity.
Molarity = (0.738 mol / 1.00 L) = 0.738 M
Step 3: Calculate the molality of KCl.
Molality = (moles of solute / mass of solvent in kg)
Since the mass of solvent is not explicitly given, we need to calculate it using the given density.
Density = mass / volume
Mass of solvent = density x volume of solvent
Volume of solvent = Volume of solution - Volume of solute
Volume of solvent = 1000 mL - 1.00 L = 1000 mL - 1000 mL = 0 mL
Mass of solvent = 1.00 g/mL x 0 mL = 0 g
Convert the mass of solvent to kg: 0 g / 1000 = 0 kg
Now we can calculate the molality:
Molality = (0.738 mol / 0 kg) = undefined
Step 4: Calculate the mole fraction of KCl.
Mole fraction of KCl = (moles of KCl / total moles of all components)
Total moles of all components = moles of solute (KCl) = 0.738 mol
Mole fraction of KCl = 0.738 mol / 0.738 mol = 1.00