Difference Between Urea and Thiourea

The key difference between urea and thiourea is that urea does not contain sulfur atoms, whereas thiourea contains sulfur atoms.

Urea and thiourea are organic compounds having a carbon atom bonded to two amine groups. These two compounds are different from each other according to the other atom bonded to the carbon atom; urea has an oxygen atom bonded to the carbon atom while thiourea compound has a sulfur atom bonded to the carbon atom.

1. Overview and Key Difference
2. What is Urea
3. What is Thiourea
4. Similarities – Urea and Thiourea
5. Urea vs Thiourea in Tabular Form
6. Summary – Urea vs Thiourea

What is Urea?

Urea is an organic compound having the chemical formula CO(NH2)2. We can name it carbamide, as well. This is a type of amide having two amine groups attached to a central carbonyl carbon atom. This molecule is a planar molecule where solid urea contains the oxygen center engaged in two N-H-O hydrogen bonds. The carbon atom in the urea molecule has sp2 hybridization. Moreover, the C-N bonds of the molecule have a significant double bond character. Furthermore, the oxygen atom in the carbonyl group has basicity when compared with formaldehyde. Furthermore, this compound has a high water solubility which reflects its ability to take part in hydrogen bonding with water molecules.

Figure 01: The Chemical Structure of Urea Molecule

Usually, urea serves an important role during the metabolism of nitrogen-consisting compounds in animals, and we can observe that this compound is the major nitrogen-containing substance in urine passed by animals. Urea is a colorless, odorless solid substance and has a high-water solubility. Practically, it is a nontoxic compound, and when it is dissolved in water, the aqueous solution of urea is neither acidic nor alkaline.

When considering the other uses of urea, it is useful in agriculture, and it is a component in nitrogen-releasing fertilizers. This because urea has a high nitrogen content, and it has a low transportation cost per unit nitrogen nutrient. Moreover, urea is important as a raw material for the production of urea-formaldehyde resins and urea-melamine-formaldehyde materials.

What is Thiourea?

Thiourea is an organosulfur compound having the chemical formula SC(NH2)2. This substance is similar to urea in its chemical structure. However, the difference in the chemical structure of urea and thiourea is the presence of an oxygen atom or a sulfur atom bonded to the carbon atom. Moreover, thiourea is considerably different from urea chemically.

Figure 02: The Chemical Structure of Thiourea

Thiourea is a planar molecule, and we can observe the weakening of the C-S chemical bond by the C-N pi bonding. These bond distances are indicated by the short C=S bond in thiobenzophenone. We can observe the thiourea occurring in two tautomeric forms: thione form and thiol form. The thione form is the predominant form in an aqueous solution. The thiol form is also named isothiourea.

Figure 03: Equilibrium Between Thione and Thiol Thiourea

When considering the applications of thiourea, it is important as a thiox precursor for the production of thiourea dioxide. It is a common reducing agent in textile processing. Moreover, this substance is important in fertilizer production.

What are the Similarities Between Urea and Thiourea?

Urea and thiourea are organic compounds
These are amines.
Both are planar molecules.

What is the Difference Between Urea and Thiourea?

Urea and thiourea are organic compounds having a carbon atom bonded to two amine groups. The key difference between urea and thiourea is that urea does not contain sulfur atoms, whereas thiourea contains sulfur atoms. Moreover, urea is important in metabolism in animals, as a component in fertilizers, in the production of urea-formaldehyde resins, etc. while thiourea is important as a thiox precursor for the production of thiourea dioxide, important for the production of fertilizers, etc.

Below is a summary of the difference between urea and thiourea in tabular form.

Summary – Urea vs Thiourea

Reference:

1. “Urea.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine.

Image Courtesy:

1. “Harnstoff” By Epark at English Wikipedia – Transferred from en.Wikipedia to Commons. (Public Domain) via Commons Wikimedia
2. “Thiourea” By Epark at English Wikipedia – Transferred from en.wikipedia to Commons. (Public Domain) via Commons Wikimedia
3. “Thiourea tautomers” By Rlcamp1 – Own work (Public Domain) via Commons Wikimedia