Question

if 4g of NaOH dissolves in 36g of H2O calculate the mole fraction of each component in the solution.also determina the molarity of solution (density of solution is 1g ml -1)

Answer 1

I hope it will help u.

Answer 2

Answer:

Molarity of the solution is 2.5 m

Explanation:

4 g of mass in NaOH = 0.1 mole of NaOH or (4/40 moles)

36 g of mass in $H_2O$ = 2 moles of H_2O or (36/18 moles)

Here, NaOH is the solute and $H_2O$ is the solvent

Formula: 1  

Using the formula for mole fraction:

Mole fraction of $H_2O$ = No of moles in $H_2O$/Total no of moles ($H_2O$+NaOH)

Total no of moles = 2 + 0.1 = 2.1

Mole fraction of $H_2O$ = 2/2.1 = 0.952

Formula: 2  

Using the formula for water:

Mole fraction of NaOH = No of moles of NaOH/Total no of moles  

Mole fraction of NaOH = 0.1/2.1 = 0.048

Mass of solution = Mass of $H_2O$ + Mass of NaOH  

= 36 + 4  = 40 g

Volume of solution = Mass of solution/Density of solution  

= 40/1 = 40 mL

Molarity of the solution = No of moles of NaOH/Volume of solution L  

= 0.1/0.04 L = 2.5 m