Question

Assertion
$HN{O_3}$ is stronger acid than $HN{O_2}$.
Reason
In $HN{O_3}$ there is two nitrogen to oxygen bonds whereas in $HN{O_2}$ there is only one.
A.Both Assertion and Reason are correct and the reason is the correct explanation for Assertion
B.Both Assertion and Reason are correct but the reason is not the correct explanation for the assertion.
C.The assertion is correct but the Reason is incorrect
D.The assertion is incorrect but Reason is correct

Answer 1

In chemistry, there are many acids and bases that exist with their different properties. Some are strong and some are weak according to their pH values. According to Bronsted-Lowry acid-base theory, we got conjugate acid and conjugate base.

Complete answer:
Bronsted-Lowry acid-base - When acid and base react, the acid forms its conjugate base and the base forms its conjugate acid.
Conjugate acid - When acid donates ${H^ + }$ion to the base is known as conjugate acid.
Conjugate base - When protons are removed from acid.
We have two acids $HN{O_3}$ and $HN{O_2}$
Here, the conjugate base of $HN{O_3}$ is $N{O_3}^ -$ and conjugate base of $HN{O_2}$ is $N{O_2}^ -$ .
$N{O_3}^ -$ is a more stable conjugate base than $N{O_2}^ -$ . And strong acid has a stable conjugate base.
Therefore, $HN{O_3}$ is stronger than $HN{O_2}$ . So, the assertion is correct.
$HN{O_3}$ - $H - \mathop {\mathop O\limits^{..} }\limits_{..} - \mathop {\mathop {\mathop {\mathop N\limits_| }\limits_O }\limits^{||} }\limits^O$ $HN{O_2}$ - $H - \mathop {\mathop O\limits^{..} }\limits_{..} - \mathop {\mathop N\limits^{||} }\limits^O$

Here, $HN{O_3}$ has three nitrogen to oxygen bonds while $HN{O_2}$ has two nitrogen to oxygen bonds. Therefore, the reason is incorrect.
So, option C is the correct answer here.

Note: Bronsted-Lowry theory was given by Johannes Nicolaus Bronsted and Thomas Martin Lowry in 1923. A cation can be a conjugate acid and an anion can be a conjugate base. The strength of conjugate acid is directly proportional to the dissociation constant.