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Question
How many moles of electrons are required for reduction of 2 moles of Zn2+ to Zn?
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Solution
The balanced equation for the reduction of Zn2+ to Zn is
\[\ce{Zn^{2+}_{ (aq)} + 2e- -> Zn_{(s)}}\]
The equation shows that 1 mole of Zn2+ is reduced to Zn by 2 moles of electrons.
For reduction of 2 moles of Zn2+, 4 moles of electrons will be required.
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