Question

144g of KCl dissolved in 1000cm3of water at 90oC. Calculate the solubility of KCl at this temperature. (K=39, Cl=35.5, 1dm3=1000cm3).

Answer 1

Answer:

The solubility of KCl is 1.93 mol/dm³

Explanation:

The information given are;

The mass of the potassium chloride, KCl = 144 g

The volume of the water solvent = 1000 cm³ = 1 dm³

The temperature of the solvent = 90 °C

The atomic mass of potassium, K = 39 u

The atomic mass of chlorine, Cl = 35.5 u

The number of moles of potassium in one mole of potassium chloride, KCl = 1 mole

The number of moles of chlorine in one mole of potassium chloride, KCl = 1 mole

The molar mass of the potassium chloride = 39 + 35.5 = 74.5 g/mol

The number of moles, n, of potassium chloride, KCl in 144 g of potassium chloride, KCl is given as follows

n = Mass/(Molar mass) = 144/74.5 = 1.93 moles

1.93 moles will dissolve in 1 dm³

Therefore, the solubility of KCl is 1.93 mol/dm³.