Stiban

Structural formula
General
Surname	Stiban
other names	Antimony hydride Antimony trihydride Antimony hydrogen Monostibane Stibine
Molecular formula	SbH 3
Brief description	colorless, unpleasantly foul-smelling gas
External identifiers / databases
CAS number 7803-52-3 EC number 620-578-3 ECHA InfoCard 100.149.507 PubChem 9359 ChemSpider 8992 Wikidata Q59712
properties
Molar mass	124.77 g mol −1
Physical state	gaseous
density	2.16 g cm −3 (liquid, −17 ° C)
Melting point	−88.5 ° C
boiling point	−17 ° C
Vapor pressure	82.8 kPa (−23 ° C)
solubility	slightly soluble in water (200 ml l −1 ) soluble in ethanol and carbon disulfide
Dipole moment	0.4 · 10 −30 C · m
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 220-280-330 P: ?
MAK	Switzerland: 0.1 ml m −3 or 0.5 mg m −3
Thermodynamic properties
ΔH f 0	145 kJ / mol
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Stiban ( monostiban or antimony hydrogen , outdated also known as stibine ), chemical formula SbH ₃ , is a colorless, foul-smelling and extremely poisonous gas that is formed when salt-like antimonides are dissolved in water and dilute acids.

Extraction and presentation

Stiban is obtained from soluble antimony compounds and nascent hydrogen . The reaction of antimony (III) hydroxide with nascent hydrogen produces stibane and water. Before this, the nascent hydrogen is obtained with zinc and hydrochloric acid, for example.

${\displaystyle \mathrm {Zn+2\ HCl\longrightarrow 2\ H_{nasc}+ZnCl_{2}} }$

${\displaystyle \mathrm {Sb(OH)_{3}+6\ H_{nasc}\to SbH_{3}+3\ H_{2}O} }$

Another option is to dissolve magnesium antimonide in an excess of dilute hydrochloric acid .

${\displaystyle \mathrm {Mg_{3}Sb_{2}+6\ HCl\to 2\ SbH_{3}+3\ MgCl_{2}} }$

However, both methods have the disadvantage that the resulting gas mainly consists of hydrogen. However, by cooling the gas to below −17 ° C, it can be separated off, since stibane condenses at this temperature.

One method that does not have this disadvantage is the hydrogenation of antimony (III) chloride using sodium borohydride in a hydrochloric acid solution.

${\displaystyle \mathrm {SbCl_{3}+3\ NaBH_{4}\longrightarrow \ SbH_{3}+3\ NaCl+3\ BH_{3}} }$

properties

Physical Properties

The melting point is −88 ° C, the boiling point is −17 ° C. The Gibbs energy is 148 kJ / mol, the standard entropy 233 J / (mol K) and the heat capacity 41 J / (mol K). Stiban is a pyramidal molecule with the three hydrogen atoms at the triangular pyramid base and the antimony atom at the top. The angles H-Sb-H are 91.7 °, the distance Sb-H is 1.707 Å . ${\displaystyle \Delta _{f}G_{g}^{0}}$ ${\displaystyle S_{g}^{0}}$ ${\displaystyle C_{pg}^{0}}$

Chemical properties

The chemical properties of stiban are similar to arsine . Typically for a heavy metal hydride, stibane is more unstable than the respective elements. The gas decomposes slowly at room temperature, but very quickly at 200 ° C. This process is autocatalytic and potentially explosive.

${\displaystyle \mathrm {2SbH_{3}\to 3H_{2}+2Sb} }$

With strong bases , stiban can be deprotonated with the formation of antimonides .

use

Stiban is used in the semiconductor industry for n-doping of silicon .

safety instructions

Due to its high toxicity and high flammability, caution is advised when handling Stiban. It should be handled with protective clothing and a protective mask, away from open flames and sparks.

Inhaling Stiban can cause coughing , nausea , sore throats and headaches , fatigue, bloody urine and shortness of breath . Damage to the blood , liver , kidneys and central nervous system can occur, which can lead to death.

Because of its instability, Stiban should not be stored if possible.

proof

Stiban can be detected with the Marsh test . For this purpose, Stiban, mixed with hydrogen, is passed through a thin glass tube drawn out to a point, and at the end it is flared. The glass tube is heated with a Bunsen burner , whereby an antimony mirror is formed in the presence of stiban in the glass tube. The antimony level differs from an arsenic level in its darker color; it is also insoluble in sodium hypochlorite solution and turns orange with polysulfide solution .

literature

• AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 .
• G. Jander, E. Blasius: Textbook of analytical and preparative inorganic chemistry . 15th edition. S. Hirzel Verlag, Stuttgart / Leipzig 2002, ISBN 3-7776-1146-8 .
• Entry to antimony hydrogen. In: Römpp Online . Georg Thieme Verlag, accessed on June 13, 2014.

Individual evidence

1. ↑ ^{a b c d e f} Entry on Stiban in the GESTIS substance database of the IFA , accessed on February 1, 2016 (JavaScript required)
2. ↑ L. Berka, T. Briggs, M. Millard, W. Jolly: The preparation of stibine and the measurement of its vapor pressure. In: Journal of Inorganic and Nuclear Chemistry. 14, 1960, pp. 190-194, doi : 10.1016 / 0022-1902 (60) 80257-6 .
3. ↑ ^{a b} Entry on antimony hydrogen. In: Römpp Online . Georg Thieme Verlag, accessed on June 13, 2014.
4. ↑ ^{a b c} G.H. Aylward, TJV Findlay: Chemistry data collection in SI units . 3. Edition. Wiley-VCH, 1999, ISBN 3-527-29468-6 .
5. ↑ Swiss Accident Insurance Fund (Suva): Limit values ​​- current MAK and BAT values (search for 7803-52-3 or Stiban ), accessed on November 2, 2015.
6. ^ Practical course in inorganic chemistry / tin - Wikibooks, collection of free textbooks, non-fiction and specialist books. Retrieved August 27, 2018 .