Answer:
mass of water = 958 g = 0.958 kg
m = 1.48 mol/kg
Explanation:
Given:
MM(KCl)= 74.54 g/mol
M= 1.417 mol/L
density of solution= 1064 g/L
To calculate the mass of water in 1 L of solution, first we have to multiply the molarity of the solution (M) by the molecular weight of KCl (MM):
1.417 mol/L x 74.54 g/mol = 105.62 g/L
As the density of the solution is 1064 g/L, we know that 1 L is equal to 1064 g. So, we have 105.62 g of KCl in 1064 g of solution. The mass of water will be the difference between the mass of solution and the mass of solute:
mass of water (g) = 1064 g - 105.6 g = 958.4 g
mass of water (kg)= 958.4 g x 1 kg/1000 g = 0.958 kg
To determine the molality (m):
m = moles of KCl/kg water
m = 1.417 moles/0.958 kg = 1.479 mol/kg
