Question

The molar mass of NaOH is 40.00 g/mol. If 5.20 g NaOH are dissolved in 0.500 L of solution, what is the molarity of the solution?

Answer 1

Answer: The molarity of the solution is 0.26M

Explanation: Molarity of the solution is defined as the number of moles of solute present in a liter volume of solution.

Mathematically,

`Molarity=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}`

Number of moles is expressed by using the formula:

`Moles=\frac{\text{Given mass}}{\text{Molar mass}}`

Putting this in above equation, we get:

`Molarity=\frac{\text{Given mass of solute (in grams)}}{\text{Molar mass of solute}*\text{volume of solution (in L)}}`

Given mass of solute (NaOH) = 5.20 g

Molar mass of solute (NaOH) = 40 g/mol

Volume of solution = 0.500 L

Putting values in above equation, we get:

`Molarity=(5.20g)/(40g/mol* 0.5L)=0.26mol/L`

Answer 2

Answer is 0.26

Molarity of the solution is

[ 5.20g / 0.5L ] x [1mole / 40.00g] =0.26