In Bi₂O₃ + 3C → 2Bi + 3CO, how many electrons are gained per bismuth atom during reduction?
Bi (+3 in Bi₂O₃) becomes 0 in Bi. Change = 0 - (+3) = -3; each Bi gains 3 electrons.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Redox Titrations and Equivalent Weight and Normality