Question

The solubility of manganese(II) sulphate at 20oC is 62.9g/100g H2O. How many grams of manganous(II)sulphate penta-hydrate crystal must be added to 51L H2O to make a saturated solution?

Answer 1

Well you gots `51*L` water.....and you need approx. `51*kg` of the hydrate.....

Explanation:

And we got `51*Lxx1000*g*"water"*L^-1xx(62.9*g*"salt")/(100*g*"water")`

`=32079*g`

And so we need to add a trifle over `32*kg` with respect to `MnSO_4(s)`.....i.e. `(32.08xx10^3*g)/(152.0*g*mol^-1)=211.05*mol`.

And with respect to the pentahydrate, this represents a mass of....

`211.05*molxx241.05*g*mol^-1=50.9*kg`....

And by the way what does `"saturated solution"` mean?