Question

Which of the following has the highest normality?
A) \[1M\,{H_2}S{O_4}\]
B) \[1M\,{H_3}P{O_3}\]
C) \[1M\,{H_3}P{O_4}\]
D) \[1M\,HN{O_3}\]

Answer 1

Hint: ormality is defined as a unit that helps in the measurement of the concentration of a solution. It is often used in titration reactions and is abbreviated as ‘N’. It is also known as equivalent concentration.

Formula used: The formula to calculate normality is as follows:
\[Normality = Molarity \times {n_{factor}}\]
\[Normality = Molarity \times \,basicity\] ,
if the basicity is to be found, we can count the number of \[{H^ + }\] ions in the acid molecule that it can donate.
\[Normality = Molarity \times Acidity\]
To calculate the acidity of the molecule we can count the number of \[O{H^ - }\] ions that a base can donate.
In the question mentioned above, all of the chemical compounds have the same molarity, the chemical substance with the greatest \[{n_{factor}}\] will have the highest normality.

Complete Step by Step Solution:
1) For \[1M\,{H_2}S{O_4}\] ,
\[Basicity = 2 = {n_{factor}}\]
2) For \[1M\,{H_3}P{O_3}\]
\[Basicity = 2 = {n_{factor}}\]
3) For \[1M\,{H_3}P{O_4}\]
\[Basicity = 3 = {n_{factor}}\]
4) For \[1M\,HN{O_3}\]
\[Basicity = 1 = {n_{factor}}\]
So \[{H_3}P{O_4}\] will have the highest normality in the question mentioned above.
Hence, option (C) will be the correct answer

Note: Normality is used in mostly three situations such as:
1) It is used to determine concentrations in the acid and base chemistry
2) It is used in precipitation reactions to determine the number of ions which, after a reaction will form into precipitate
3) It is also often used in the redox reactions. It helps to determine the number of electrons a reducing agent can donate or the number of electrons that the oxidising agent can accept.
Apart from the above applications, normality also has certain limitations such as it requires the determination of a proper equivalence factor and its value is not specific and can often change on the basis of the chemical reaction.