When 0.066 mole of sodium (Na) is completely reacted with water according to the equation 2 Na + 2 H_2O → 2 NaOH + H_2, how many moles of hydrogen gas (H_2) are produced?

• A. 0.033 mole
• B. 0.066 mole
• C. 0.132 mole
• D. 0.0165 mole

Answer: (A)

Verified step by step guidance

1. Write down the balanced chemical equation: \[2\ Na + 2\ H_2O \rightarrow 2\ NaOH + H_2\]
2. Identify the mole ratio between sodium (Na) and hydrogen gas (H_2) from the balanced equation. For every 2 moles of Na, 1 mole of H_2 is produced.
3. Set up a proportion using the mole ratio to find the moles of hydrogen gas produced from 0.066 moles of sodium: \[\frac{2\ \text{moles Na}}{1\ \text{mole H}_2} = \frac{0.066\ \text{moles Na}}{x\ \text{moles H}_2}\]
4. Solve for \[x\], the moles of hydrogen gas produced, by cross-multiplying and dividing: \[x = \frac{0.066 \times 1}{2}\]
5. Interpret the result as the number of moles of hydrogen gas produced when 0.066 moles of sodium react completely with water.