Write the formula for Tetramminediaquacobalt (III) Chloride

$[Co(NH_3)_4(H_2O)_2]Cl_3$

The correct answer is Option (4) → $[Co(NH_3)_4(H_2O)_2]Cl_3$.

The correct formula for Tetramminediaquacobalt(III) chloride is \([Co(NH_3)_4(H_2O)_2]Cl_3\).

Understanding the Name:

Tetrammine indicates there are four ammonia (NH₃) ligands.

Diaqua indicates there are two water (H₂O) ligands.

Cobalt(III) indicates that cobalt has a +3 oxidation state.

Chloride indicates that the compound contains chloride ions (Cl⁻).

Building the Complex:

The central metal ion is cobalt (Co) in the +3 oxidation state.

There are four ammonia ligands and two water ligands attached to the cobalt.

The overall charge of the complex ion must balance with the three chloride ions.

Thus, the overall formula for the complex is:

\([Co(NH_3)_4(H_2O)_2]Cl_3\)

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