Question

Calculate Molarity of a $63\%w/wHN{O}_3$ solution if density is $1.4g/mL$ .

• A. $14M$
• B. $12M$
• C. $10M$
• D. $8M$

Answer 1

The correct option is A $14M$

$Molarity$ : The number of moles of a solute dissolved in $1L\left(1000mL\right)$ of the solution is known as the molarity of the solution.
$\text{Molarity}=\frac{\text{mass of solute (g)}}{\text{Molar mass of solute (g)}}\times \frac{1000}{\text{Volume of solution (ml)}}$
$\text{Molarity}=\frac{\text{\%}w/w\times density\times 10}{M{M}_{solute}}=\frac{63\times 1.4\times 10}{63}=14M$

Hence, the correct answer is option (a).