Q118 · Practice questionComplex familiar1 mark
QUESTION 118
An acidic hydrogen fuel cell consumes 0.0300 mol of oxygen. Assuming all of this oxygen forms water, how many moles of electrons pass through the external circuit?
(A)
0.0150 mol
(B)
0.0300 mol
(C)
0.120 mol
(D)
0.0600 mol
WORKED SOLUTION
1 markAnswer C
Answer
C
Working
The cathode equation is . Each oxygen molecule accepts four electrons, giving 4 × 0.0300 = 0.120 mol.
Marking criteria
- Select C. [1 mark]
Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.
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