The density of `10% ` by mass of KCI solution in water is ` 1 . 0 6 g mL^(-1)` . Calculate molarity and molality of the solution

Answer

1.43 M

Explanation

Mass of `100%` solution = 100 g(say)
`:.`Mass of KCI = 10 g
Volume of solution `= ("Mass")/("Density") = (100 g)/( 1 . 06 g mL^(-1))`
`= 94 . 34 mL = 0.09434 L`
No. of moles of solute `= (10 g)/( 74 . 5 g mol^(-1))`
= 0.134 mol
Molar mass of KCI
`= (39 + 35 . 5) g mol^(-1) = 374 . 5 g mol^(-1)`
Molarity of solution `=("mole of solute ")/("Volume of solution (L)")`
`= (0 .134 mol)/( 0.0943 L)`
`= 1.23 mol L^(-1) = 1.423 M`