First, identify the reactants and products involved in the reaction. The given species are carbonate ion (\(\mathrm{CO}_{3}^{2-}\)) and carbonic acid (\(\mathrm{H}_{2}\mathrm{CO}_{3}\)).
Step 2: Write the Unbalanced Equation
Write the unbalanced chemical equation for the reaction between carbonate ion and carbonic acid:
\[
\mathrm{CO}_{3}^{2-} + \mathrm{H}_{2}\mathrm{CO}_{3} \rightarrow \text{Products}
\]
Step 3: Determine the Products
In aqueous solution, carbonate ion (\(\mathrm{CO}_{3}^{2-}\)) can react with carbonic acid (\(\mathrm{H}_{2}\mathrm{CO}_{3}\)) to form bicarbonate ion (\(\mathrm{HCO}_{3}^{-}\)) and water (\(\mathrm{H}_{2}\mathrm{O}\)).
Step 4: Write the Balanced Equation
Balance the chemical equation by ensuring the number of atoms of each element and the charges are equal on both sides of the equation:
\[
\mathrm{CO}_{3}^{2-} + \mathrm{H}_{2}\mathrm{CO}_{3} \rightarrow 2 \mathrm{HCO}_{3}^{-}
\]