Question

28 g KOH (molar mass = 56) is dissolved in 500 mL solution. Calculate the molarity of the solution.

Hint:

Always convert volume into litres before applying the molarity formula.

Answer 1

Step 1: Calculate number of moles of KOH.
\[ n = \frac{\text{Mass of solute}}{\text{Molar mass}} = \frac{28}{56} = 0.5 \, \text{mol} \]

Step 2: Convert volume of solution into litres.
\[ V = 500 \, \text{mL} = 0.500 \, \text{L} \]

Step 3: Apply molarity formula.
\[ M = \frac{n}{V} = \frac{0.5}{0.500} = 1.0 \, M \]
\[ \boxed{\text{Molarity of the solution = 1.0 M}} \]