Question

Ferrocene is:

• A. \( Fe(\eta^5 - C_5H_5)_2 \)
• B. \( Fe(\eta^2 - C_5H_5)_2 \)
• C. \( Cr(\eta^5 - C_5H_5)_5 \)
• D. \( Os(\eta^5 - C_5H_5)_2 \)

Hint:

Ferrocene exhibits aromatic stability and undergoes electrophilic substitution reactions like benzene.

Answer 1

The Correct Option is A

Step 1: Ferrocene Definition
Ferrocene is an organometallic compound featuring an iron (Fe\(^2+\)) core.
It is structured with two cyclopentadienyl (\( C_5H_5^- \)) rings sandwiching the metal center.
Step 2: Bonding Characteristics
The hapticity (\(\eta^5\)) signifies that all five carbon atoms within each ring engage with the metal.
This configuration results in a stable and symmetrical molecular arrangement.
Final Answer: The chemical formula for ferrocene is \( Fe(\eta^5 - C_5H_5)_2 \).