Question

Calculate the mole fraction of the ionic species kcl in the solution.

Answer 1

The question is incomplete, here is the complete question:

Calculate the mole fraction of the ionic species KCl in the solution A solution was prepared by dissolving 43.0 g of KCl in 225 g of water.

Answer: The mole fraction of KCl in the solution is 0.044

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$      .....(1)

• For water:

Given mass of water = 225 g

Molar mass of water = 18 g/mol

Putting values in equation 1, we get:

$\text{Moles of water}=\frac{225g}{18g/mol}=12.5mol$

• For KCl:

Given mass of KCl = 43 g

Molar mass of KCl = 74.55 g/mol

Putting values in equation 1, we get:

$\text{Moles of KCl}=\frac{43g}{74.55g/mol}=0.577mol$

Mole fraction of a substance is given by:

$\chi_A=\frac{n_A}{n_A+n_B}$

• For KCl:

Moles of KCl = 0.577 moles

Total moles = [0.577 + 12.5] = 13.077 moles

Putting values in above equation, we get:

$\chi_{(KCl)}=\frac{0.577}{13.077}=0.044$

Hence, the mole fraction of KCl in the solution is 0.044