Which of the following species has the maximum number of unpaired electrons?
Correct answer: A. O2
- A. O2
- B. O+2
- C. O-2
- D. O2-2
Explanation
O2 has 2 unpaired electrons, O+2 has no unpaired electrons, O-2 has paired electrons while O2-2 also has no unpaired electrons hence the correct option is A The number of unpaired electrons in an atom or ion can be determined by examining its electron configuration. Let's analyze the given species: 1. **O2**: Molecular oxygen (O2) has a total of 16 electrons (8 electrons per oxygen atom). Its electron configuration is 1s² 2s² 2p⁴. There are two unpaired electrons in the 2p orbital. 2. **O+2**: Oxygen cation (O+2) is formed by losing two electrons from O2. Its electron configuration becomes 1s² 2s² 2p³. There is one unpaired electron in the 2p orbital. 3. **O-2**: Oxygen anion (O-2) is formed by gaining two electrons by O2. Its electron configuration becomes 1s² 2s² 2p⁶. There are no unpaired electrons. 4. **O2-2**: This is a hypothetical species, as it would mean adding two more electrons to O-2, which is not energetically favorable. If you meant O-2, please refer to the explanation for O-2 above. Based on the analysis, **O2** has the maximum number of unpaired electrons with **two unpaired electrons**.
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