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प्रश्न
Calculate the mass of sodium sulphate required to prepare its 20% (mass percent) solution in 100g of water?
उत्तर
Let the mass of sodium Sulphate required to be = x g
The mass of solution would be = (x + 100) g x g of solute in (x + 100) g of solution
20% = `"x"/("x" + 100) xx 100`
20x + 2000 = 100x
80x = 2000
x = `200/80`
= 25g
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