Determine the mass of water to be added to 50 ml of sulfuric acid with a density of 1.8 g / ml with a mass fraction of 90% to obtain a 9% solution.
m (H2SO4 substance) = 50 x 1.8 x 0.9 = 81 g
m (H2SO4 solution) = 50 x 1.8 = 90 g
81 g – 9%
x g – 100%
x = (81 x 100) / 9 = 900 g
m (added water) = 900-90 = 810 g.
Answer: you need to add 810 g of water.
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