Hardness of water is 200 ppm. Calculate the molarity and normality of `CaCO_(3)` of the water

Options

A. `4 xx 10^(-3) M, 2 xx 10^(-3)N`
B. `2 xx 10^(-6) M, 4 xx 10^(-3)N`
C. `2 xx 10^(-3)M, 4 xx 10^(-3)N`
D. `1 xx 10^(-3)M, 4 xx 10^(-3)N`

Answer

C

Explanation

200ppm mean 200g in `10^(6)` mL solution
Molarity `=(wt)/(M.w) xx (1000)/(V_(mL)) = (200)/(100) xx (1000)/(10^(6))`
`= 2 xx 10^(-3)M`
Normality `= (200)/(50) xx (1000)/(10^(6))`
`= 4 xx 10^(-3) N`