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Calculate the molality and molarity of a solution made by mixing equal volumes of `30%` by weight of `H_(2)SO_(4)` (density`=1.20g//ml`) and `70%` by weight of `H_(2)SO_(4)` (density`=1.60g//mL`) |
Answer» Correct Answer - Molality `=11.44 m`, Molarity `=7.55M` Suppose that the solution contains `100 ml` of each variety of `H_(2)SO_(4)`. Total solution is, `200 ml` or `0.2` litre `wt.` of `100 ml` of `H_(2)SO_(4)` solution `(30%)=1060xx100=160` gram `wt.` of `H_(2)SO_(4)(30%)=120xx(30)/(100)=36` gram `wt.` of `H_(2)SO_(4)(70%)=160xx(70)/(100)=112` gram Total `wt.` of `H_(2)SO_(4)` (salute) `=36+112=148` gram `therefore wt.` of `H_(2)O`(solvent) `=wt.` of solution`-wt.` of solute `=(120+160)-148` `=280-148=132` gram Moles of `H_(2)SO_(4)=(148)/(98)=1.51` (mol `wt.` of `H_(2)SO_(4)=98`) Molality `=(1.51)/(132)xx1000=11.44m` Molarity `=(1.51)/(0.2)=7.55 M` |
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