Sulphur

Step 1: Understand the bonding in .
In molecules, each sulfur atom forms two single bonds with neighboring sulfur atoms in a cyclic structure. The sulfur atoms in are surrounded by four electron pairs, suggesting that the sulfur atoms undergo hybridization.

Step 2: Analyze the hybridization.
- : This hybridization occurs when an atom forms three sigma bonds and one lone pair. This is not applicable to sulfur in .
- : This is the correct hybridization for sulfur in , as each sulfur atom forms four sigma bonds (two with other sulfur atoms and two lone pairs).
- : This is incorrect as sulfur does not form two bonds in .
- : This hybridization involves the use of d-orbitals, but sulfur in does not require such orbitals for bonding.

Step 3: Conclusion.
The correct answer is (2), , because each sulfur atom in undergoes hybridization.

Step 1: Understanding the Concept:
EAN (Effective Atomic Number) = Atomic number - (oxidation state) + 2 (number of ligands). CO is neutral ligand.
Step 2: Detailed Explanation:
For Fe(CO) in zero oxidation state: EAN = 26 + 2x = 36 2x = 10 x = 5.
Formula = Fe(CO) . Iron pentacarbonyl.
Step 3: Final Answer:
Thus, .

Concept: Stability of sulphur oxyacids depends on bonding and oxidation states.

Step 1: Check structure II.
HO–SO –OH is not a valid stable structure.

Step 2: Check structure IV.
HS–SO –OH is unstable due to improper bonding.

Step 3: Conclusion.
Both II and IV do not exist.