Question

Which one of the following molecules attains greater stability on formation of its diatomic monovalent anion?

• A. C\(_2\)
• B. O\(_2\)
• C. N\(_2\)
• D. F\(_2\)

Hint:

When considering the stability of diatomic molecules' anions, it is important to account for the electronic structure and how well the molecule can stabilize the additional electron.

Answer 1

The Correct Option is A

Step 1: Analyze the formation of monovalent anions.
When molecules form their monovalent anions, the stability of these anions depends on how well the added electron is stabilized by the molecular orbitals. A molecule that can stabilize an added electron will form a more stable anion.

Step 2: Consider the electronic configuration and stability.
- C\(_2\): In the case of C\(_2\), the addition of an electron results in the filling of the molecular orbitals in a way that the system becomes more stable. This is because C\(_2\) has a relatively simple electronic structure that allows the added electron to be stabilized effectively.
- O\(_2\): For O\(_2\), adding an electron results in a less stable configuration because the additional electron enters a higher energy orbital and increases electron-electron repulsion.
- N\(_2\): Similarly, N\(_2\) has a stable bonding arrangement, and the addition of an electron results in a less stable anion due to electron repulsion.
- F\(_2\): The addition of an electron to F\(_2\) leads to a highly unstable anion because fluorine is already highly electronegative, and adding an electron only increases repulsion in the system.

Step 3: Conclusion.
The molecule that attains greater stability on formation of its diatomic monovalent anion is C\(_2\), as it can effectively stabilize the added electron. Therefore, the correct answer is option (A).