MCQ
Note : In the following questions a statement of assertion $(A)$ followed by a statement of reason $(R)$ is given. Choose the correct option out of the choices given below each question.
Assertion $(A)$ : Redox couple is the combination of oxidised and reduced form of a substance involved in an oxidation or reduction half cell.
Reason $(R)$ : In the representation $\text{E}^\ominus_{\text{Fe}^{3+}/\text{Fe}^{2+}}$ and $\text{E}^\ominus_{\text{Cu}^{2+}/\text{Cu}},\text{Fe}^{3+}/\text{Fe}^{2+}$ and $\text{Cu}^{2+}/\text{Cu}$ are redox couples.
  • A
    $A$ and $R$ both are correct, and $R$ is the correct explanation of $A.$
  • $A$ and $R$ both are correct, but $R$ is not the correct explanation of $A$.
  • C
    $A$ is true but $R$ is false.
  • D
    $A$ and $R$ both are false.

Answer

Correct option: B.
$A$ and $R$ both are correct, but $R$ is not the correct explanation of $A$.
A redox couple is defined as pair of compounds or elements having together the oxidised and reduced forms of it and taking part in an oxidation or reduction half reaction.

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