To a solution of calcium chloride weighing 90 g with a mass fraction of 5% was added 10 g of the same salt. Mass

To a solution of calcium chloride weighing 90 g with a mass fraction of 5% was added 10 g of the same salt. Mass fraction of salt in the resulting solution is equal to

ω = m (substance) / m (solution) (1)
Find the mass of the substance in the first solution:
m (substance) = 90 * 0.05 = 4.5g
Find the mass of the substance in the second solution:
m (substance) = 14.5g
Find the mass of the solution:
m = 90 + 10 = 100g
Substitute the values in the formula (1)
ω = 0.145 = 14.5%

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