Thiourea

From Sciencemadness Wiki
Revision as of 20:31, 2 January 2020 by Mabus (Talk | contribs) (Chemical)

Jump to: navigation, search
Thiourea
Names
IUPAC name
Thiourea
Preferred IUPAC name
Thiourea
Other names
Thiocarbamide
Properties
CH4N2S
SC(NH2)2
Molar mass 76.12 g/mol
Appearance White crystalline solid
Odor Odorless
Density 1.405 g/cm3
Melting point 182 °C (360 °F; 455 K)
Boiling point Decomposes
13.7 g/100 ml (25 °C)
14.2 g/100 ml (25 °C)
Solubility Reacts with acids
Soluble in ethanol, methanol
Almost insoluble in diethyl ether, hexane
Solubility in ethanol 3.6 g/100 ml (20 °C)
4.7 g/100 ml (31.9 °C)
6.3 g/100 ml (45 °C)
8.5 g/100 ml (58 °C)
9.8 g/100 ml (64.7 °C)
Solubility in methanol 11.9 g/100 ml (25 °C)
16.4 g/100 ml (40.7 °C)
22 g/100 ml (53.7 °C)
24.6g/100 ml (61.9 °C)
Thermochemistry
Hazards
Safety data sheet Sigma-Aldrich
Lethal dose or concentration (LD, LC):
1,750 mg/kg (rat, oral)
Related compounds
Related compounds
Urea
N-Allylthiourea
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Thiourea is an organosulfur compound with the formula SC(NH2)2. It is structurally similar to urea, except that the oxygen atom is replaced by a sulfur atom, thus the properties of urea and thiourea differ significantly.

Properties

Chemical

Oxidation of thiourea with hydrogen peroxide produces thiourea dioxide

Physical

Thiourea is a colorless white solid, soluble in water. It is odorless and has a taste, often described as bitter. It sublimes under vacuum between 150-160 °C.

Availability

Thiourea is sold by many lab and chemical suppliers.

The liquid silver cleaning product TarnX contains thiourea, a detergent and sulfamic acid.

Preparation

Thiourea can be easily produced from ammonium thiocyanate via heat treatment at 180 °C.

Industrially it is produced by the reaction of hydrogen sulfide with calcium cyanamide in the presence of carbon dioxide.

Projects

  • Make thiourea peroxide
  • Silver polishing
  • Preparation of pharmaceuticals
  • Auxiliary agent in diazo paper
  • Reducing peroxides to the corresponding diols
  • Converting alkyl halides to thiols

Handling

Safety

Thiourea displays average toxicity. The LD50 values given in literature are between 125 and 1,750 mg/kg for rats (oral dose).

A goitrogenic effect (enlargement of the thyroid gland) has been reported for chronic exposure, reflecting the ability of thiourea to interfere with iodide uptake.[1]

Storage

In closed plastic bottles.

Disposal

Thiourea can be neutralized with a strong oxidizing solution.

References

  1. https://onlinelibrary.wiley.com/doi/abs/10.1002/14356007.a26_803

Relevant Sciencemadness threads