Which one of the following group 16 elements does not exist in -2 oxidation sate ?

Options

A. S
B. Se
C. O
D. Po

Explanation

To solve the question "Which one of the following group 16 elements does not exist in -2 oxidation state?", we will follow these steps:

### Step 1: Identify Group 16 Elements
Group 16 elements in the periodic table include:
- Oxygen (O)
- Sulfur (S)
- Selenium (Se)
- Tellurium (Te)
- Polonium (Po)

### Step 2: Understand Oxidation States
In chemistry, oxidation states indicate the degree of oxidation of an atom in a compound. The -2 oxidation state is common for nonmetals in Group 16, particularly for oxygen, sulfur, selenium, and tellurium.

### Step 3: Analyze the Trend in Group 16
As we move down the group from oxygen to polonium:
- The atomic size increases.
- Electronegativity decreases.

### Step 4: Determine the Tendency to Show -2 Oxidation State
- Oxygen, sulfur, selenium, and tellurium readily form compounds in the -2 oxidation state due to their higher electronegativity.
- Polonium, being a heavier element and a metalloid, has a much lower tendency to gain electrons and does not typically exhibit a -2 oxidation state.

### Step 5: Conclusion
Based on the analysis, polonium (Po) does not exist in the -2 oxidation state.

### Final Answer:
The element from Group 16 that does not exist in -2 oxidation state is **Polonium (Po)**.

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