3.6g mixture of sodium chloride and potassium chloride is dissolved in water. The solution is treated with excess of silver nitrate solution, 7.74g of silver chloride is obatined. Find the percentage of sodium chloride and potassium chloride in the mixture.

Explanation

The balanced equation between in `NaCl and AgNO_(3)`
`underset(58.8g)underset(1"mol")(NaCL)+AgNO_(3) to underset(143.5g)underset(1"mol")(AgCl_(3))+NaNO_(3)`
Let x g of NaCl be present in the mixture.
58.5g NaCl produce= 143.5g AgCl
x g NaCl will produce=`(143.5)/(58.5)xx xgAgCl`
The balanced equation between KCl and `AgNO_(3)` is:
`underset(74.5g)underset(1"mol")(KCl)+AgNO_(3) to underset(143.5g)underset(1"mol")(KCl)(AgCl)+KNO_(3)`
KCl present in the mixture=(3.60-g)
74.5g of Cl produce=143.5g of AgCl
(3.6-x)g of KCl will produce=`(143.5)/(74.5)xx(3.6-x)g of AgCl`
`"Thus", (143.5)/(58.5)x+(143.5)/(74.5)x+(143.5)/(74.5)(3.6x-x)=7.74`
x=1.54
`% "of NaCl"=(1.54)/(3.60)xx100=42.7`
`% "of KCl"=((1.54-3.60))/(3.60)xx100=57.3`