Question

Which element from following exhibits anomalous behavior with remaining three members?

• A. \(\text{F}\)
• B. \(\text{Cl}\)
• C. \(\text{Br}\)
• D. \(\text{I}\)

Hint:

The first member of a group differs because of its small size and high electronegativity.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept
The first element of a p-block group often behaves differently from the rest because of small size, high electronegativity and absence of d orbitals.

Step 2: Apply to halogens
Fluorine is the smallest and most electronegative halogen.
It shows only the oxidation state \(-1\), forms very strong hydrogen bonds in HF and has an unusually weak F-F bond.

Step 3: Compare the options
Chlorine, bromine and iodine show similar trends and variable oxidation states.
So fluorine is anomalous.

Final Answer:
Fluorine is the anomalous halogen. \[ \boxed{\text{(A) }\text{F}} \]