Question

In the half-reaction 2H 2 O(l)→O 2 (g)+4H + (aq)+4e −

, if 0.076 L of O2 is collected at 25°C and 755 mmHg, how many moles of electrons passed through the solution?

a. 0.0038 moles
b. 0.0076 moles
c. 0.0114 moles
d. 0.0152 moles

Answer 1

The number of moles of electrons passed through the solution is 0.0038 moles.

Step-by-step explanation:

To determine the number of moles of electrons passed through the solution, we can use the stoichiometry of the half-reaction. In the given half-reaction 2H2O(l) → O2(g) + 4H+(aq) + 4e-, we see that for every 4 moles of electrons produced, 1 mole of O2(g) is formed. Therefore, if 0.076 L of O2(g) is collected, we can set up a ratio:

4 mol e- / 1 mol O2(g) = x mol e- / 0.076 L O2(g)

Solving for x, we find that x = 0.0038 moles of electrons passed through the solution.