Question

The soft Lewis base(s) is(are)

• A. \( I^- \)
• B. CO
• C. \( H^- \)
• D. \( \text{CH}_3\text{NC} \)

Hint:

Soft bases like \( H^- \) donate electrons easily due to their low charge density and ease of interaction with soft acids.

Answer 1

The Correct Option is A, B, C, D

Step 1: Understanding soft and hard acids and bases (SHAB).
According to the SHAB principle, soft acids prefer to bond with soft bases, and hard acids prefer to bond with hard bases. Soft bases typically have low charge density, and thus tend to donate electrons more easily.

Step 2: Analyzing the options.
- \( I^- \): Iodide is a soft base, but \( H^- \) is softer.
- CO: Carbon monoxide is a hard base.
- \( H^- \): Hydride is the softest among the given options.
- \( \text{CH}_3\text{NC} \): Methyl isocyanide is a harder base.

Step 3: Conclusion.
The soft Lewis base is (C) \( H^- \).