Answer:
A) Oxidized
B) Reduced
C) Oxidized
D) Oxidized
Step-by-step explanation:
A) Cu becomes Cu²⁺
oxidation state increased from 0 to +2. It gets oxidize.
B) Sn⁺⁴ becomes Sn²⁺
oxidation state decreased from +4 to +2. It gets reduced.
C) Cr³⁺ becomes Cr⁺⁶
oxidation state increased from +3 to +6. It gets oxidize.
D) Ag becomes Ag⁺
oxidation state increased from 0 to +1. It gets oxidize.
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Consider the following reactions.
4KI + 2CuCl₂ → 2CuI + I₂ + 4KCl
the oxidation state of copper is changed from +2 to +1 so copper get reduced.
CO + H₂O → CO₂ + H₂
the oxidation state of carbon is +2 on reactant side and on product side it becomes +4 so carbon get oxidized.