You are given standard electrode potential `(E^@)`
`Zn^2//Zn=-0.76V,Na^(+)//Na =-2.71V`
`Mg^(2+)//Mg=-2.36 V,K^+//K=-2.93V`
Which one is the strongest reducing agent ?

Options

A. Mg
B. K
C. Zn
D. Na

Answer

To determine which of the given metals is the strongest reducing agent, we need to analyze the standard electrode potentials (E°) provided for each metal. The standard electrode potentials are as follows:

- \( E°(Zn^{2+}/Zn) = -0.76 \, V \)
- \( E°(Na^+/Na) = -2.71 \, V \)
- \( E°(Mg^{2+}/Mg) = -2.36 \, V \)
- \( E°(K^+/K) = -2.93 \, V \)

### Step 1: Understand the Concept of Reducing Agents
A reducing agent is a substance that donates electrons in a chemical reaction and is oxidized in the process. The strength of a reducing agent is inversely related to its standard reduction potential (E°). A lower (more negative) E° value indicates a stronger tendency to lose electrons (be oxidized), thus acting as a stronger reducing agent.

### Step 2: Compare the Standard Electrode Potentials
From the values given:
- Zinc: \( -0.76 \, V \)
- Sodium: \( -2.71 \, V \)
- Magnesium: \( -2.36 \, V \)
- Potassium: \( -2.93 \, V \)

### Step 3: Identify the Lowest E° Value
Among the given values, potassium has the lowest standard reduction potential at \( -2.93 \, V \).

### Step 4: Conclusion
Since potassium has the lowest E° value, it is the strongest reducing agent among the four metals listed.

Thus, the answer is:
**Potassium (K) is the strongest reducing agent.**

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