Answer:
Step-by-step explanation:
Here, we want to balance the given equation in acidic conditions
We start by breaking the equation into half equations
We have that as:
![\begin{gathered} ClO_3^-\text{ }\rightarrow\text{ Cl}^- \\ NO_2\rightarrow\text{ NO}_3^- \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/high-school/v5vx8dc99bbgx91pgy2ed74zdvvi669o7c.png)
The next step is to balance other elements aside from oxygen and hydrogen
This is already done
The next step is to balance oxygen by adding H2O:
![\begin{gathered} ClO_3^-\text{ }\rightarrow\text{ Cl}^-\text{ +3 H}_2O \\ NO_2\text{ + H}_2O\text{ }\rightarrow NO_3^-\text{ } \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/high-school/lljaipl6a242an3drmavkfhioalmbt7cm3.png)
The next step is to balance hydrogen by adding the hydrogen ion
We have that as:
![\begin{gathered} ClO_3^-\text{ + 6H}^+\text{ }\rightarrow Cl^-\text{ + 3H}_2O \\ NO_2\text{ + H}_2O\text{ }\rightarrow\text{ NO}_3^-\text{ + 2H}^+ \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/high-school/s5q33apyus3pc8dzkgdbc4o79z59rxjs18.png)
The next step here is to balance the excess ions by adding electrons:
![\begin{gathered} ClO_3^-\text{ + 6H}^+\text{ + 4e}^-\rightarrow\text{ Cl}^-\text{ + 3H}_2O \\ NO_2\text{ + H}_2O\text{ }\rightarrow\text{ NO}_3^-\text{ + 2H}^+\text{ + e}^- \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/high-school/mm6dsewo6ery106ux7pq0gjr2feofffjyp.png)
Now, we need to cancel out the electrons.
We multiply equation ii by 4:
![\begin{gathered} ClO_{3\text{ }}^-\text{ + 6H}^+\text{ + 4e}^-\text{ }\rightarrow\text{ Cl}^-\text{ + 3H}_2O \\ 4NO_2\text{ + 4H}_2O\text{ }\rightarrow\text{ 4NO}_3^-\text{ + 8H}^+\text{ + 4e}^- \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/high-school/dglbw24p0w7j9kxlcxq8pm8i46ryqqqob1.png)
Now, let us merge the two equations:
![ClO_3^-\text{ + 4NO}_2\text{ + H}_2O\text{ }\rightarrow\text{ Cl}^-\text{ + 4NO}_3^-\text{ + 2H}^+](https://img.qammunity.org/2023/formulas/chemistry/high-school/8f8d57gav6et897jfavchygrkkw26wpsp6.png)