If one mole of CO_2 reacts completely with excess NaOH according to the equation CO_2 + 2 NaOH → Na_2CO_3 + H_2O, how many moles of NaOH are required?

• A. 1 mole
• B. 0.5 moles
• C. 2 moles
• D. 4 moles

Answer: (C)

Verified step by step guidance

1. Identify the balanced chemical equation given: \(\mathrm{CO_2 + 2\ NaOH \rightarrow Na_2CO_3 + H_2O}\).
2. Note the mole ratio between \(\mathrm{CO_2}\) and \(\mathrm{NaOH}\) from the balanced equation. For every 1 mole of \(\mathrm{CO_2}\), 2 moles of \(\mathrm{NaOH}\) are required.
3. Since the problem states that 1 mole of \(\mathrm{CO_2}\) reacts completely, use the mole ratio to find the moles of \(\mathrm{NaOH}\) needed: multiply 1 mole of \(\mathrm{CO_2}\) by the ratio \(\frac{2\ moles\ NaOH}{1\ mole\ CO_2}\).
4. Calculate the product of the mole ratio and the given moles of \(\mathrm{CO_2}\) to determine the moles of \(\mathrm{NaOH}\) required.
5. Conclude that the number of moles of \(\mathrm{NaOH}\) required corresponds to the stoichiometric coefficient in the balanced equation multiplied by the moles of \(\mathrm{CO_2}\) reacted.