key term - Oxalate

Definition

Oxalate is a dianion with the chemical formula C2O4^{2-}, formed from oxalic acid and commonly found in various plants. It acts as a ligand in coordination compounds, meaning it can bind to metal ions, influencing the structure and properties of the resulting complex. Understanding oxalate's role is crucial for grasping how it interacts in coordination chemistry, particularly in the nomenclature and structural formulation of coordination compounds.

5 Must Know Facts For Your Next Test

1. Oxalate can form both bidentate and chelating complexes with metal ions, allowing it to create stable coordination compounds.
2. Common metal ions that oxalate coordinates with include calcium, iron, and lead, which have significant implications in biological systems and environmental chemistry.
3. In the context of nomenclature, the oxalate ligand is named as 'oxalato' when it binds to a metal center.
4. Oxalate is often found in food sources like spinach and rhubarb, where it can form insoluble complexes with calcium, affecting nutrient absorption.
5. The formation of oxalate complexes is important in various applications, including wastewater treatment and the analysis of metal contaminants.

Review Questions

• How does oxalate function as a ligand in coordination compounds, and what type of bonding interactions does it typically exhibit?
  • Oxalate functions as a bidentate ligand, meaning it can bind to a central metal atom at two sites. This allows oxalate to form stable chelate complexes with various metal ions. The interaction occurs through the donation of electron pairs from the oxygen atoms in the oxalate anion, creating coordinate covalent bonds with the metal center. This characteristic significantly influences the geometry and stability of the coordination compound formed.
• Discuss the implications of oxalate binding with specific metal ions in biological systems and their relevance to health.
  • Oxalate's ability to form complexes with metal ions such as calcium can have important implications for human health. In the kidneys, high levels of oxalate can lead to the formation of calcium oxalate stones, which are a common type of kidney stone. Moreover, oxalate binding can inhibit calcium absorption from food sources, potentially leading to deficiencies. Understanding these interactions helps in dietary considerations and managing conditions related to mineral metabolism.
• Evaluate how the unique properties of oxalate influence its applications in environmental chemistry and industrial processes.
  • The unique properties of oxalate as a strong ligand allow it to form stable complexes with various heavy metals, making it useful in environmental chemistry for remediating contaminated water. Oxalate can help precipitate out toxic metals from waste streams through chelation processes. In industrial applications, its reactivity can be harnessed for processes like photocatalysis or as a reducing agent. By evaluating these properties, we can understand how oxalate plays a critical role in both mitigating pollution and enhancing chemical processes.

Related terms

Ligand: A molecule or ion that binds to a central metal atom in a coordination compound, influencing its properties and behavior.

Coordination Number:

The number of ligand atoms that are bonded to a central metal atom in a coordination complex, impacting its geometry and stability.

Chelate: A type of complex where a ligand wraps around a metal ion, forming multiple bonds and significantly stabilizing the metal's coordination sphere.