Calculate mass percent, mole fraction, molarity and molality?

A solution was prepared by dissolving 39.0g of KCL in 225g of water.

1. Calculate the mass percent of KCl in the solution.
2. Calculate the mole fraction of KCl in the solution.
3. Calculate the molarity of KCl in the solution if the total volume of the solution is 239mL .
4. Calculate the molality of KCl in the solution.

Answer:
1. % = (39.0 / 39.0 + 225 ) x 100 = 14.8 %

2.
Molecular weight KCl = 74.55 g/mol
39.0 / 74.55 = 0.523 moles KCl
Molecular weight H2O = 18 g/mol
225 / 18 = 12.5 moles H2O
X (KCl) = 0.523 / 0.523 + 12.5 = 0.0401

3.
V = 0.239 L
M = 0.523 / 0.239 = 2.19

4.
m = 0.523 /0.225 Kg = 2.32

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