The standard electrode potentials of four elements A, B, C and D are `-3.05, 1.66, -0.40 and 0.80` volts respectively. The highest chemical activity will be shown by:

Options

A. A
B. B
C. C
D. D

Explanation

To determine which element among A, B, C, and D has the highest chemical activity based on their standard electrode potentials, we can follow these steps:

### Step 1: Understand Standard Electrode Potential
Standard electrode potential is a measure of how easily an element can lose its electrons. A more negative value indicates that the element can lose its electrons more easily, thus showing higher reactivity.

### Step 2: List the Standard Electrode Potentials
We have the following standard electrode potentials for the elements:
- Element A: -3.05 volts
- Element B: 1.66 volts
- Element C: -0.40 volts
- Element D: 0.80 volts

### Step 3: Compare the Values
To determine which element has the highest chemical activity, we need to compare the values:
- A: -3.05 V (most negative)
- B: 1.66 V (positive)
- C: -0.40 V (less negative)
- D: 0.80 V (positive)

### Step 4: Identify the Most Reactive Element
Among the values, Element A has the most negative standard electrode potential (-3.05 V). This indicates that it can lose its outermost electron very easily compared to the other elements.

### Conclusion
Therefore, the element with the highest chemical activity is **Element A**.

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