From a solution of aluminum chloride weighing 110 g and a mass fraction of salt of 10%, 10 g of water was evaporated and 5 g of the same salt was added. Mass fraction of salt in the resulting solution is equal to
ω = m substance / (m solution)
Find the mass of aluminum chloride from the first solution of m substance = m solution * ω
m substance = 110g * 0.1 = 11g
m water = m solution – m substances = 110-11 = 99 g
By condition, 10 g of water was evaporated.
Next, 5 g of salt is added to the solution.
Thus, the final solution will contain:
water 99-10 = 89 g
aluminum chloride = 11 + 5 = 16 g
total weight = 89 + 16 = 105 g
We substitute the values in the formula ω = 16 * 100% / 105 = 15.2%
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