Question

Calculate the volume of water to be added to $500\text{mL}$ of a $2N$ solution to obtain a $0.1N$ resultant solution.

• A. $9.5\text{L}$
• B. $6.8\text{L}$
• C. $8.6\text{L}$
• D. $11.5\text{L}$

Answer 1

The correct option is A $9.5\text{L}$

$N_1{V}_1=N_2{V}_2$
Where,
$N_1\Rightarrow \text{Normality of the initial solution = 2 N}$
$V_1\Rightarrow \text{Volume of the initial solution =500 mL}$.
$N_2\Rightarrow \text{Normality of the resultant solution i.e. after dilution = 0.1 N}$
$V_2\text{= Volume of the resultant solution}$.
$2\times 500=0.1\times V_2$
$V_2=\frac{2\times 500}{0.1}=10000\text{mL}$
So, volume of water to be added
$=(10000–500)\text{mL}$
$=9500\text{mL}$
$=9.5\text{L}$