In a hydrogen-oxygen fuel cell that is operating, a separate reaction occurs at each electrode. at the hydrogen electrode: $\text{H}_2 \rightarrow 2\text{H}^+ + 2e^-$ at the oxygen electrode: $\text{O}_2 + 2\text{H}_2\text{O} + 4e^- \rightarrow 4\text{OH}^-$ The electrons released at the hydrogen electrode pass through the external circuit to the oxygen electrode, where they are accepted by the oxygen and water. A hydrogen-oxygen fuel cell is run for some time and four moles of oxygen molecules are used up. What mass of hydrogen is consumed?
- A$2.0\,\text{g}$
- B$4.0\,\text{g}$
- C$8.0\,\text{g}$
- D$16.0\,\text{g}$