(a) Amina observed that crystals of copper sulphate are formed in the solution, when a saturated solution of copper sulphate has cooled. Will the solution be still remained as
saturated? Why?
(b) Calculate the mass of sodium sulphate required to prepare its 20% (mass by mass
%) solution in water, if mass of the solution is 80 g​

See explanation

Explanation:

A saturated solution is a solution that contains just as much solute as it can normally hold at that temperature.

If the temperature is cooled and  crystals of copper sulphate are formed in the solution, then the solution is no longer saturated because some solute are now leaving the solution.

b) percent by mass = mass of solute/mass of solution * 100

percent by mass = 20%

mass of solute = x g

mass of solution =  80 g​

20 = x/80 * 100

1600 = 100x

x = 1600/100

x = 16 g

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