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How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0 M `HNO_(3)` solution ? The concentration of nitric acid is 70 % by mass. |
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Answer» No of moles `HNO_(3)=("Mass of "HNO_(3))/("Molar mass of HNO"_(3))=(W)/(("63 g mol"^(-1)))` Volume of solution in litres = 0.250 L Molarity of solution `= ("No. of moles of HNO"_(3))/("Molarity of solution in litres")` `(2.0 "mol L"^(-1))=(W)/(("63 g mol"^(-1))xx("0.250 L"))` `W=("2.0 mol L"^(-1))xx("63 g mol"^(-1))xx(0.250 L)=31.5 g` Actual mass of `HNO_(3)=(31.5g)xx(100)/(70)=45g`. |
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