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}timestext{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=frac{5.20g}{40g/moltimes 0.5L}=0.26mol/L