Calculate the molarity of Kl if the density of `20%` (mass/mass) aqueous Kl is `1.202 " g mL"^(-1)`

Options

A. `0.004M`
B. `1.25M`
C. `0.25M`
D. `1.45M`

Answer

D

Explanation

Since,density is given, so first we calculate volume and then molarity.
Let, the weight of the solution `100g`
Density of the solution `=1.202" g "mL^(-1)`
`"Volume of the solution"=("Weight of solution")/("Density")`
`=(100g)/(1.202" g "mL^(-1))=83.19mL`
`=(100g)/(1.202" g "mL^(-1))=83.19mL`
Volume of the solution=0.083 L
Molarity of the solution (M)
`=("Number of moles of Kl")/("Volume of solutionin litres")`
=`((20g)//(166" g" " mo1"^(-1)))/((0.0083L))`
`=1.45mol" L"^(-1)`
Molarity of the solution (M) =1.45 M