Determine the mass fraction of the solute if 30 g of salt was added to a 20% sodium chloride solution weighing 120 g?
| May 6, 2021 | education
Given:
m (solution) = 120 g,
m (substance) = 30 g,
W1 = 20%
W2-?
Decision:
W = m (substance): m (solution) × 100%, hence
m (substance) = (m (solution) × W): 100%.
m (substance) = (120 g × 20%): 100% = 24 g.
m (substance) = 24 g + 30 g = 54 g.
m (solution) = 54 g + 120 g = 174 g.
W = (54g: 174) × 100% = 31%.
Answer: 31%.
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