Which of the following has the highest size ?

Options

A. `S^(2-)`
B. `Se^(2-)`
C. `O^(2-)`
D. `Fe^(2-)`

Answer

To determine which element has the highest size among the given options from Group 16 (the Oxygen family), we can follow these steps:

### Step 1: Identify the Elements
First, we need to identify the elements in Group 16. The common elements in this group include:
- Oxygen (O)
- Sulfur (S)
- Selenium (Se)
- Tellurium (Te)
- Polonium (Po)

### Step 2: Understand Atomic Size Trend
In the periodic table, atomic size increases as you move down a group. This is because:
- Each successive element has an additional electron shell.
- The increased distance of the outermost electrons from the nucleus results in a decrease in the effective nuclear charge experienced by these electrons.

### Step 3: Compare the Elements
Now, let's compare the elements based on their positions in the periodic table:
- Oxygen is at the top of Group 16.
- Tellurium is further down the group.

Since atomic size increases down the group, we can conclude that Tellurium (Te) will have a larger atomic size compared to Oxygen (O), Sulfur (S), and Selenium (Se).

### Step 4: Conclusion
Among the elements in Group 16, Tellurium (Te) has the highest atomic size.

### Final Answer
The element with the highest size is **Tellurium (Te)**.

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