Question

What is the concentration of a solution containing 2.5g of potassium hydroxide in \\(250cm^{3}\\) of solution? (K=39, H=1, O=16)

Answer 1

Answer : The concentration of solution is 0.18 M

Explanation :  Given,

Mass of KOH = 2.5 g

Molar mass of KOH = 56 g/mole

Volume of solution = $250cm^3=250mL$

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

Formula used :

$\text{Molarity}=\frac{\text{Mass of }KOH\times 1000}{\text{Molar mass of }KOH\times \text{Volume of solution (in mL)}}$

In this question, the solute is KOH.

Now put all the given values in this formula, we get:

$\text{Molarity}=\frac{2.5g\times 1000}{56g/mole\times 250L}=0.18mole/L=0.18M$

Therefore, the concentration of solution is 0.18 M