The standard reduction potentials of 4 elements are given below. Which of the following will be the most suitable reducing agent.
`I=-3.04V,II=-1.90V,III=0V,IV=1.90V`

Options

A. I
B. II
C. III
D. IV

Explanation

To determine the most suitable reducing agent from the given standard reduction potentials, we can follow these steps:

### Step 1: Understand the Concept of Reducing Agents
A reducing agent is a substance that donates electrons in a chemical reaction and gets oxidized in the process. The strength of a reducing agent is inversely related to its standard reduction potential (SRP). The more negative the SRP, the better the reducing agent.

### Step 2: Identify the Standard Reduction Potentials
We have the following standard reduction potentials for the four elements:
- Element I: \( E^\circ = -3.04 \, V \)
- Element II: \( E^\circ = -1.90 \, V \)
- Element III: \( E^\circ = 0 \, V \)
- Element IV: \( E^\circ = 1.90 \, V \)

### Step 3: Compare the Standard Reduction Potentials
To find the most suitable reducing agent, we need to identify which element has the most negative standard reduction potential:
- Element I: \( -3.04 \, V \) (most negative)
- Element II: \( -1.90 \, V \)
- Element III: \( 0 \, V \)
- Element IV: \( 1.90 \, V \) (most positive)

### Step 4: Determine the Most Suitable Reducing Agent
From the comparison, we can see that Element I has the most negative standard reduction potential of \( -3.04 \, V \). Therefore, it is the best reducing agent among the four options.

### Conclusion
The most suitable reducing agent is **Element I** with a standard reduction potential of \( -3.04 \, V \).

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