Chemistry
Grade-10
Easy
Question
Which of the following half reactions correctly represents a reduction half reaction?
- Fe →Fe2+ + 2e-
- Pb4+ + 2e- →Pb2+
- 2O-2 →O2 + 4e-
- Fe + 3e- →Fe3+
Hint:
Lowering of oxidation state is reduction.
The correct answer is: Pb4+ + 2e- →Pb2+
Reduction is the transfer of electrons between species in a chemical reaction where there is a process of gaining electrons or a decrease in the oxidation state by an element. A reduction chemical reaction involves increasing electrons associated with a single atom or a group of atoms.
Pb4+ + 2e- →Pb2+
Oxidation state of lead reduces from +4 to +2.
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