Question

What is the volume strength of $1$M solution of ${H_2}{O_2}$ ?

Answer 1

Hint: The volume strength of hydrogen peroxide solution is equal to the volume of oxygen gas released by $1$ volume solution.

Complete step by step answer:
The term “volume strength” is only used for hydrogen peroxide. Hydrogen peroxide solution having one volume strength means one volume solution of ${H_2}{O_2}$ will release one volume of oxygen.
Decomposition of ${H_2}{O_2}$ to ${O_2}$ can be written as,
$2{H_2}{O_2} \to 2{H_2}O + {O_2}$
This means two moles of ${H_2}{O_2}$ gives one mole of ${O_2}$ on decomposition.
One mole of every substance occupies a volume of $22.4$ L at STP. Then two moles of every substance occupy $2 \times 22.4 = 44.8$ L at STP.
From the equation we can say that $44.8$ L ${H_2}{O_2}$ gives $22.4$ L ${O_2}$.
We need to calculate the volume strength of $1$ M solution of ${H_2}{O_2}$ . $1$ M solution of ${H_2}{O_2}$ contains $1$ mole ${H_2}{O_2}$ in $1$ L solution.
From the equation we understand that, $1$ mole of ${H_2}{O_2}$ will give $0.5$ mole of ${O_2}$. In other words, $1$ mole of ${H_2}{O_2}$ will give $\dfrac{{22.4}}{2} = 11.2$ L ${O_2}$.
Here, the amount of ${H_2}{O_2}$ we have is one mole. Therefore, the volume of oxygen released from the given solution of ${H_2}{O_2}$ will be $11.2$ L. Since the concentration is $1$ M, the volume of the solution is $1$ L. i.e. $1$ L of ${H_2}{O_2}$ gives $11.2$ L of oxygen.
$1$ L of $1$ mole of ${H_2}{O_2}$ gives $11.2$ L of oxygen.
i.e. $1$ M solution of hydrogen peroxide gives $11.2$ L oxygen.
Hence the volume strength of $1$M solution of ${H_2}{O_2}$ is $11.2$ .
Hence option B is correct.

Note:
We can solve this question in another way. First we need to determine the volume of oxygen liberated by one mole of ${H_2}{O_2}$. Then multiply this number with molarity of solution. Then we will get the volume strength of the given solution.