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Redox and electrochemistry — Question 105

Original QCE Vault practice · 1 mark

Q105 · Practice questionSimple familiar1 mark

QUESTION 105

A cell potential calculated from standard reduction potentials differs from the potential measured for the same pair of half-cells. Which observation best explains the difference?

(A)
The ion concentrations were 0.020 mol L⁻¹ rather than standard concentrations.
(B)
The voltmeter was connected to the external circuit.
(C)
The reduction half-equation was multiplied by two when balancing electrons.
(D)
A salt bridge allowed ions to migrate.
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