To 250 g of 20% sulfuric acid was added 50 ml of 60% acid (density 1.6 g / ml). What is the mass fraction of acid in the resulting solution?

Find the mass of acid m = 250 * 0.2 + 50 * 1.6 * 0.6 = 98 g
Find the mass of the final solution m (solution) = 250 + 50 * 1.6 = 330 g
ω = m (substance) / m (solution) = 98 * 100/330 = 30%

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