CADMIUM SOLUBILITY AND pH Cadmium is a toxic metal. It can be removed from water by chemical precipitation of solid cadmium hydroxide, Cd(OH), The drinking water standard for cadmium is 5 μg L (0.005 mg L). The solubility product of Cd(OH), is 2 x 10" M. What is the minimum pH necessary to reduce the dissolved cadmium ion concentration to the standard?

Explanation:

It is known that,

      Molar mass of Cd = 112.41 g/mol

Standard concentration of Cd = 0.005 mg/L = g/L

Hence, we will calculate the molarity as follows.

        Molarity =

                       = M

Equation for the reaction is as follows.

          M

Also,

                      =

                      =

Relation between pH and concentration of hydrogen ions is as follows.

               pH =

                     =

                     = 10.82

Thus, we can conclude that a minimum pH of 10.82 is necessary to reduce the dissolved cadmium ion concentration to the standard.

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.