Question

Calculate the mass of sodium sulphate required to prepare its 20% mass/mass percentage solution of 100g of water

Answer 1

Mass % of Sodium sulphate in the solution = 20%
Mass % of water = 100 - 20 = 80 %

If the total mass of the solution = 100 g

100 per cent of solution is 100/80 gm

20 per cent of solution is (100/80) x 20 = 25 gm

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