What is a redox couple?

Explanation

### Step-by-Step Solution:

1. **Definition of Redox Couple**:
A redox couple refers to a pair of chemical species that exist in two different oxidation states, specifically the oxidized form and the reduced form of a substance.

2. **Components of a Redox Couple**:
In a redox couple, the oxidized form is the species that has lost electrons (is oxidized), while the reduced form is the species that has gained electrons (is reduced).

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