The reduction potential values are given below
`Al^(3_)//Al =- 1.67 "volt" Mg^(2+)//Mg =- 2.34 "volt" Cu^(2+)//Cu = +0.34` volt
`I_(2)//2I^(-) = +0.53` volt. Which one is the best reducing agent?

Options

A. `Al`
B. `Mg`
C. `Cu`
D. `I_(2)`

Explanation

To determine the best reducing agent from the given reduction potential values, we can follow these steps:

### Step 1: Understand the concept of reduction potential
Reduction potential indicates the tendency of a species to gain electrons and be reduced. A lower (more negative) reduction potential means that the species is more likely to lose electrons and thus act as a reducing agent.

### Step 2: List the given reduction potentials
The reduction potentials provided are:
- \( Al^{3+}/Al = -1.67 \, \text{V} \)
- \( Mg^{2+}/Mg = -2.34 \, \text{V} \)
- \( Cu^{2+}/Cu = +0.34 \, \text{V} \)
- \( I_2/2I^- = +0.53 \, \text{V} \)

### Step 3: Identify the lowest reduction potential
From the listed values, we can see:
- \( Al^{3+}/Al = -1.67 \, \text{V} \)
- \( Mg^{2+}/Mg = -2.34 \, \text{V} \) (lowest)
- \( Cu^{2+}/Cu = +0.34 \, \text{V} \)
- \( I_2/2I^- = +0.53 \, \text{V} \)

The lowest reduction potential is for magnesium (\( Mg^{2+}/Mg \)) at -2.34 V.

### Step 4: Conclude which is the best reducing agent
Since magnesium has the lowest reduction potential, it is the best reducing agent among the given options. This means magnesium is more likely to lose electrons and reduce other species.

### Final Answer:
**The best reducing agent is \( Mg \).**

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