Substance profile
Thiourea
Thiourea is a white solid which crystallizes in a rhombic bipyramidal structure and is odorless.
01 · Identification
What Thiourea is
Thiourea is a white solid which crystallizes in a rhombic bipyramidal structure and is odorless. It boils at 155 °C, melts at 182 °C.
Under the GHS it carries the signal word Warning. It is classed as carcinogens.
Other names for Thiourea
- thiocarbamide
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H351 | Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H361d | Suspected of damaging the unborn child. |
| H302 | Harmful if swallowed. |
| H411 | Toxic to aquatic life with long lasting effects. |
Precautionary statements: P201, P270, P273, P280, P301, P308, P312, P313, P330, P391, P501
03 · Physical and chemical properties
Thiourea properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 155 °C (311 °F) | range, midpoint shown | CAMEO |
| Decomposes at boiling point | decomposes | HSDB | |
| Melting point | 182 °C (359.6 °F) | ICSC | |
| 178 °C (352.4 °F) | DOE PAC | ||
| 177 °C (350.6 °F) | range, midpoint shown | HSDB | |
| Density | 1.4 g/cm³ | ICSC | |
| 1.405 g/cm³ | at 20 °C | CAMEO | |
| 1.405 g/cm³ | at 25 °C | HSDB | |
| Solubility | Soluble in alcohol; sparingly soluble in ether. | HSDB | |
| In water, 1.42X10+5 mg/L at 25 °C | at 25 °C | HSDB | |
| Soluble in water at 25 °C: 1 part in 11 | at 25 °C | HSDB | |
| Vapor pressure | 1.41e-7 mmHg | at 25 °C | HSDB |
| 0.0028 mmHg | Haz-Map |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Thiourea
Storage conditions
Keep container tightly closed in a dry and well-ventilated place. Handle and store in inert gas. Storage class (TRGS 510): Non Combustible Solids.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
The solid peroxide produced by action of hydrogen peroxide & nitric acid on thiourea (& possibly a hydrogen peroxidate of thiourea dioxide) decomposed violently on drying in air, with evolution of sulfur dioxide & free sulfur.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
THIOUREA is a white crystalline material or powder, toxic, carcinogenic. When heated to decomposition it emits very toxic fumes of oxides of sulfur and oxides of nitrogen. Violent exothermic polymerization reaction with acrylaldehyde (acrolein) [MCA SD-85, 1961], violent decomposition of the reaction product with hydrogen peroxide and nitric acid [Bjorklund G. H. et al., Trans. R. Soc. Can.,1950, 44, p. 28], spontaneous explosion upon grinding with potassium chlorate [Soothill, D., Safety Management, 1992, 8(6), p. 11].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Thiourea in the storage compatibility matrix →