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प्रश्न
How much water should be mixed with 12 mL of alcohol so as to obtain 12 % alcohol solution ?
उत्तर
Volume of solute = 12 ml
Volume of solution = volume of solute + volume of solvent
Volume of solvent = volume of solution – volume of solvent = 100 – 12 = 88 ml
`"Concentration" = "Volume of solute"/"volume of solute + mass of solvent"xx 100`
`12 =12/(12 + x)xx100`
`x=88`
So, 88 ml of water will be added to 12 ml of alcohol in order to prepare a concentration 12%.
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