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In its standard state arsine is a colorless, denser-than-air gas that is slightly soluble in water (2% at 20 °C) [1] and in many organic solvents as well. [citation needed] Arsine itself is odorless, [5] but it oxidizes in air and this creates a slight garlic or fish-like scent when the compound is present above 0.5 ppm. [6]
On roasting arsenopyrite in air, arsenic sublimes as arsenic(III) oxide leaving iron oxides, [52] while roasting without air results in the production of gray arsenic. Further purification from sulfur and other chalcogens is achieved by sublimation in vacuum, in a hydrogen atmosphere, or by distillation from molten lead-arsenic mixture.
Arsenic(V) acid is a weak acid and the salts are called arsenates, [5] the most common arsenic contamination of groundwater, and a problem that affects many people. Synthetic arsenates include Scheele's Green (cupric hydrogen arsenate, acidic copper arsenate), calcium arsenate, and lead hydrogen arsenate.
1625 – First description of hydrogen by Johann Baptista van Helmont. First to use the word "gas". 1650 – Turquet de Mayerne obtains a gas or "inflammable air" by the action of dilute sulphuric acid on iron. 1662 – Boyle's law (gas law relating pressure and volume). 1670 – Robert Boyle produces hydrogen by reacting metals with acid.
Cavendish discovered hydrogen as a colorless, odourless gas that burns and can form an explosive mixture with air, and published a paper on the production of water by burning inflammable air (that is, hydrogen) in dephlogisticated air (now known to be oxygen), the latter a constituent of atmospheric air (phlogiston theory).
Arsenic sublimes at 615 °C (1137 °F), passing directly from the solid state to the gaseous state. [21] Antimony melts at 631 °C (1167 °F) [21] Platinum melts at 1768 °C (3215 °F), even higher than iron. [21]
Arsine decomposes to arsenic and hydrogen at 250–300 °C, stibine to antimony and hydrogen at room temperature, and bismuthine to bismuth and hydrogen above −45 °C. Arsine and stibine are very easily oxidised to arsenic or antimony trioxide and water; a similar reaction happens with sulfur or selenium. Reaction with metals at elevated ...
The purification of arsenic was later described in the works attributed to the Muslim alchemist Jabir ibn Hayyan (c. 850 –950). [22] Albertus Magnus ( c. 1200 –1280) is typically credited with the description of the metal in the West, [ 41 ] though some question his work and instead credit Vannoccio Biringuccio , whose De la pirotechnia ...