Question

What volume of $2M$ ${H_2}S{O_4}$ is required to form $0.2N$ of $100ml$ of solution?
(a)5ml
(b)20ml
(c)10ml
(d)50ml

Answer 1

There is a very close relation between normality and $$ molarity, while molarity refers to the concentration of a compound or ion, normality refers to the molar concentration only of the acid component or only of the base component of the solution.

Complete Step By Step Answer:
The mole equivalent of an acid-base are calculated by determining the number of ${H^ + }$ or $O{H^ - }$ ions per molecules, the formula for Normality will be:
$N = n \times M$ (Where n is the number of ${H^ + }$ ions for acid solution or number of $O{H^ - }$ ions for base solution.)
We can say that the Normality of sulfuric acid is:
$Normality = 2 \times 2 = 4N$
The number of ${H^ + }$ ions is two because there are two atoms of hydrogen present in sulfuric acid.
The equation of normality that helps to estimate the volume of a solution required to prepare a solution of different normality. We can use the formula:
${N_1}{V_1} = {N_2}{V_2}$
Where, ${N_1}$ is the initial normality, ${V_1}$ Is the initial volume, ${N_2}$ is the normality of the final solution and ${V_2}$ is the volume of the final solution.
Therefore, $4 \times {V_1} = 0.2 \times 100$
${V_1} = 5ml$
Therefore, $5ml$ of $2M$ ${H_2}S{O_4}$ is required.
Option $(a)\;5ml$ is correct.

Note:
Titration is the process of gradual addition of a solution of a known concentration and volume with another solution of unknown concentration until the reaction approaches its neutralization. Normality and molarity are two important and commonly used expressions in chemistry. They are used to indicate the quantitative measurement of a substance.