Coordination Chemistry

To calculate the Effective Atomic Number (EAN), use the following equation: Considering the complex :
- The atomic number of cobalt is 27.
- The oxidation state of cobalt in the complex is +3.
- The coordination number, representing the number of ligands bound to cobalt, is 6.
Applying these values to the formula:

Anisole can be converted to phenol via hydrolysis using hydrobromic acid:
Neon (Ne) is a noble gas with various applications. Two important uses include:
1. Illumination: Used in neon lights and advertising signs.
2. Cryogenics: Used in high-performance cooling systems, especially in refrigeration.

Acetaldehyde can be converted to isopropyl alcohol through the following steps:
1. Aldol Condensation:
2. Catalytic Hydrogenation: Thus, acetaldehyde undergoes aldol condensation followed by hydrogenation to yield isopropyl alcohol.

Cumene is converted to phenol by the cumene hydroperoxide process:
1. Oxidation of Cumene:
2. Acidic Hydrolysis: Thus, cumene is oxidized to cumene hydroperoxide, which undergoes acid hydrolysis to give phenol and acetone as a byproduct.

The given IUPAC name is sodium hexanitrocobaltate(III).
- "Hexanitro-" refers to six ligands.
- "Cobaltate" indicates the presence of a complex anion.
- The oxidation state of cobalt is (III), meaning .
- The charge of requires three ions for charge neutrality.
Thus, the correct formula is , making the correct answer (c).

- Oxidation State of Ni: So, Ni is in the oxidation state.
- Electronic Configuration of :
- Nature of Ligand:
- Cyanide is a strong field ligand, which causes pairing of electrons.
- The square planar geometry is preferred.
- Unpaired Electrons & Hybridization:
- Hybridization:
- Unpaired electrons: 0
- Geometry: Square Planar

- Oxidation State of Ni: Thus, Ni is in the oxidation state.
- Electronic Configuration of :
- Nature of Ligand:
- Chloride is a weak field ligand, so it does not cause strong pairing.
- The tetrahedral geometry is favored.
- Unpaired Electrons & Hybridization:
- Hybridization:
- Unpaired electrons: 2
- Geometry: Tetrahedral