key term - [Co(NH3)5SO4]Br

Definition

[Co(NH3)5SO4]Br is a coordination compound consisting of a cobalt ion coordinated to five ammonia molecules and one sulfate ion, with bromide serving as a counterion. This complex highlights the fascinating world of isomerism, where different structural arrangements can exist for coordination compounds, affecting their physical and chemical properties.

5 Must Know Facts For Your Next Test

1. The cobalt in [Co(NH3)5SO4]Br has a coordination number of 6 due to five ammonia ligands and one sulfate ligand being attached to it.
2. This complex can exhibit geometric isomerism because of the arrangement of ligands around the cobalt center, leading to different spatial configurations.
3. The presence of the sulfate ion (SO4^2-) as part of the complex introduces potential for ion pairing with the bromide (Br^-), impacting solubility and reactivity.
4. Ammonia is a neutral ligand, which influences the overall charge of the coordination complex; since Br^- is negatively charged, the overall charge of [Co(NH3)5SO4] must be +1.
5. Isomers of this coordination compound can have distinct properties, such as differences in solubility or color, which are crucial for applications in areas like catalysis and materials science.

Review Questions

• How does the coordination number affect the structure and properties of [Co(NH3)5SO4]Br?
  • The coordination number of [Co(NH3)5SO4]Br is 6, meaning that cobalt is surrounded by six donor atoms from five ammonia ligands and one sulfate ion. This high coordination number leads to a specific geometry around the cobalt center, typically octahedral in this case. The arrangement influences not only the stability of the complex but also its reactivity, color, and how it interacts with other substances.
• Discuss how geometric isomerism could manifest in the coordination compound [Co(NH3)5SO4]Br.
  • [Co(NH3)5SO4]Br can exhibit geometric isomerism due to the arrangement of ligands around the cobalt center. For example, if the sulfate ion occupies different positions relative to the ammonia ligands (such as facial or meridional arrangements), distinct isomers can form. These different spatial configurations will result in variations in properties such as solubility and color, which are significant in practical applications and studies of these compounds.
• Evaluate the implications of counterions like Br^- on the behavior and application of coordination complexes such as [Co(NH3)5SO4]Br.
  • Counterions like Br^- play a crucial role in influencing the overall behavior and applications of coordination complexes. In [Co(NH3)5SO4]Br, bromide acts as a balancing ion that affects solubility in various solvents, which is vital for reactions in solution. Furthermore, these counterions can participate in secondary interactions that alter stability and reactivity. The choice of counterion can thus affect how these complexes are used in catalysis, pharmaceuticals, or material synthesis.

Related terms

Coordination Number:

The number of ligand atoms that are directly bonded to the central metal ion in a coordination complex.

Ligand:

A molecule or ion that can donate a pair of electrons to a central metal ion to form a coordination complex.

Geometric Isomerism:

A type of isomerism where compounds with the same molecular formula have different spatial arrangements of their atoms or groups.