Difference Between Oxalate and Oxalic Acid

The key difference between oxalate and oxalic acid is that oxalate is an anion whereas oxalic acid is an organic compound.

Oxalate is the conjugate base of oxalic acid. However, the formation of oxalic acid is a step-wise reaction, which gives a collection of few compounds known as oxalic acid.

1. Overview and Key Difference
2. What is Oxalate
3. What is Oxalic Acid
4. Side by Side Comparison – Oxalate vs Oxalic Acid in Tabular Form
5. Summary

What is Oxalate?

Oxalate is an anion having the chemical formula C₂O₄^2-. It is a dianion because it is a combination of two charged species that we can write as (COO)₂^2-. We can abbreviate this ion as “ox”. Furthermore, it can occur as an anion in ionic compounds or as a ligand in coordination compounds. However, the conversion of oxalate into oxalic acid is a complicated and step-wise reaction.

Difference Between Oxalate and Oxalic Acid

Figure 01: Structure of Oxalate

Furthermore, the molar mass of this ion is 88 g/mol. When considering the structure of this anion, the geometry can be either planar or staggered structure according to the X-ray crystallographic analysis.

What is Oxalic Acid?

Oxalic acid is an organic compound having the chemical formula H2C2O4. It is a colourless solid which easily dissolves in water. It is a dicarboxylic acid because it is a combination of two carboxylic acid groups; in fact, it is the simplest dicarboxylic acid. Moreover, it has a high acid strength and it is a strong reducing agent. The conjugate base of this acid is oxalate ion.

Figure 02: Structure of Oxalic Acid

Typically, this acid occurs in the dihydrate form. Moreover, it naturally occurs in some food. The molar mass of the anhydrous form is 90 g/mol.

What is the Difference Between Oxalate and Oxalic Acid?

The key difference between oxalate and oxalic acid is that oxalate is an anion whereas oxalic acid is an organic compound. Furthermore, the molar mass of oxalate is 88 g/mol while the molar mass of oxalic acid is 90g/mol. The conjugate acid of oxalate ion is oxalic acid while the conjugate base of oxalic acid is oxalate.

Summary – Oxalate vs Oxalic Acid

Oxalate is the anion that originates from oxalic acid. Oxalic acid is an organic compound. The key difference between oxalate and oxalic acid is that oxalate is an anion whereas oxalic acid is an organic compound.

Reference:

1. “Oxalic Acid.” Wikipedia, Wikimedia Foundation, 12 Sept. 2019, Available here.

Image Courtesy:

1. “Oxalate-ion-2D-skeletal” By Kemikungen – Own work, Public Domain) via Commons Wikimedia
2. “Oxalsäure2” By NEUROtiker – Own work, Public Domain) via Commons Wikimedia