Hybridization in [Cr(NH3)6]Cl2
Hybridization in coordination complexes plays a crucial role in determining the geometry and properties of the complex. In [Cr(NH3)6]Cl2, the central chromium atom is surrounded by six ammonia ligands and two chloride ions.

Central Atom: Chromium (Cr)
- Chromium has an electronic configuration of [Ar] 3d5 4s1.
- The oxidation state of chromium in this complex is +3.

Ligands: Ammonia (NH3) and Chloride (Cl-)
- Ammonia ligands are neutral and act as strong-field ligands.
- Chloride ions are negatively charged ligands.
- Ammonia ligands are considered as strong ligands, leading to a high spin complex.

Hybridization of Chromium
- The coordination number of chromium in this complex is 6.
- The d-orbitals of chromium (3d) undergo hybridization with the s-orbital to form sp3d2 hybridization.
- The six ligands occupy the six hybrid orbitals around the central chromium atom.

Geometry of the Complex
- Due to the presence of six ligands, the complex adopts an octahedral geometry.
- The ammonia ligands are arranged in an octahedral fashion around the central chromium atom.
In conclusion, the hybridization in [Cr(NH3)6]Cl2 is sp3d2, and the complex exhibits an octahedral geometry. Understanding the hybridization in coordination complexes is essential for predicting their structures and properties in various chemical reactions.