Write balanced net ionic equation for the following reactions in acidic solution:
\[HN{{O}_{2}}(aq)\to NO_{3}^{-}+NO(g)\]

Hint: To balance a chemical reaction in an acidic medium we have to add one water molecule to balance the one oxygen atom and to balance hydrogen we should add one hydrogen cation on the opposite side of the chemical reaction.

Complete answer:
- In the question it is given that to write a balanced chemical reaction for \[HN{{O}_{2}}(aq)\to NO_{3}^{-}+NO(g)\] in acidic medium.
- The given imbalanced chemical reaction is as follows.
\[HN{{O}_{2}}(aq)\to NO_{3}^{-}+NO(g)\]
- First we have to balance the number of nitrogen atoms in the given chemical reaction.
\[2HN{{O}_{2}}(aq)\to NO_{3}^{-}+NO(g)\]
- In the above chemical reaction the oxidation state of the nitrogen atom is going to change from +3 to +5.
- Therefore the overall change in the oxidation number is +2.
- To balance this we should write the chemical reaction as follows.
\[3HN{{O}_{2}}(aq)\to NO_{3}^{-}+2NO(g)\]
- Now in the above chemical reaction the number of nitrogen atoms is balanced. Now we have to balance the number of oxygen atoms on both sides and it is as follows.
\[3HN{{O}_{2}}(aq)\to NO_{3}^{-}+2NO(g)+{{H}_{2}}O\]
- Now in the above chemical reaction the number of oxygen atoms is balanced and now we have to balance the number of hydrogen atoms on the both sides of the above chemical reaction by adding hydrogen ions on the side where the number of hydrogens are less and it is as follows.
\[3HN{{O}_{2}}(aq)\to NO_{3}^{-}+2NO(g)+{{H}_{2}}O+{{H}^{+}}\]
- The balanced chemical reaction of the given equation in acidic medium is as follows.
\[3HN{{O}_{2}}(aq)\to NO_{3}^{-}+2NO(g)+{{H}_{2}}O+{{H}^{+}}\]

Note:
We have to make sure that in which medium the chemical reaction has to be balanced. In the basic medium to balance the number of hydrogen atoms we are supposed to add hydroxide ions on the side where less number of hydrogens are present.