(1) equal to the number of electrons gained (2) equal to the number of protons gained (3) less than the number of electrons gained (4) less than the number or protons gained
In oxidation-reduction reactions, the number of electrons lost is equal to the number of electrons gained. This is due to the conservation of charge that requires a balance between the two processes of oxidation and reduction. Thus, option 1 is the correct answer.
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