Determine the concentrations of mgcl2, mg2+, and cl− in a solution prepared by dissolving 2.852.85 × 10−4 g mgcl2 in 2.252.25 l of water. express all three concentrations in molarity. additionally, express the concentrations of the ionic species in parts per million (ppm).

Answer : The concentration of are 0.127 ppm, 0.127 ppm and 0.254 ppm respectively.

Explanation : Given,

Mass of =

Volume of solution = 2.25 L

First we have to calculate the concentration in terms of g/L.

conversion used :

As we know that,

1 mg/L = 1 ppm

0.127 mg/L = 0.127 ppm

So, the concentration will be 0.127 ppm.

The concentration of in ppm is, 0.127 ppm.

Now we have to calculate the concentration of and .

We assume that, dissociates 100 % in the solution then the balanced reaction will be:

From the reaction we conclude that the mole ratio of is, 1 : 1 : 2. So,

The concentration of = 0.127 ppm

The concentration of = 2 × 0.127 ppm = 0.254 ppm

the ratio of the conjugate base to the acid required to attain the desired ph.