Given :
`Co^(3+) + e^(-) to Co^(2+)` , `E^(@) = +1.81V`
`pb^(4+) + 2e^(-) rightarrow Pb^(2+)` , `E^(@) = + 1.67V`
`Ce^(4)+ e^(-)rightarrow Ce^(3+), E^(@) = +1.61V`
`Ce^(4)+3e^(-)rightarrow Bi`, `E^(@) = + 0.20V`
Oxidation power of the species will increase in the order:

Options

A. `Ce^(4+) ltPb^(4+) lt BI^(3+)ltCO^(3+)`
B. `CO^(3+)lt Ce^(4+)ltBi^(3+) lt Pb^(4+)`
C. `Bi^(3+lt Ce^(4+) ltPb^(4+) lt Co^(3+)
D. `CO^(3+)ltPb^(4+) lt Ce^(4+) lt Bi^(3+)`

Explanation

To determine the order of oxidation power of the species based on their reduction potentials, we will follow these steps:

### Step 1: Understand the Concept of Reduction Potentials
Reduction potentials (E°) indicate the tendency of a species to gain electrons (be reduced). A higher E° value means a stronger oxidizing agent, as it has a greater tendency to be reduced and thus can oxidize other species more effectively.

### Step 2: List the Given Reduction Potentials
We have the following reduction reactions and their corresponding E° values:
1. \( \text{Co}^{3+} + e^- \rightarrow \text{Co}^{2+} \), \( E° = +1.81 \, \text{V} \)
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