Ammonium chloride
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| Ammonium chloride | |
|---|---|
| Image:Ammonium chloride.jpg | |
| General | |
| Systematic name | Ammonium chloride |
| Chemical formula | NH4Cl |
| Appearance | white crystalline powder |
| Physical | |
| Formula weight | 53.4913 |
| Melting point | 338°C (640F) sublimes |
| Boiling point | 520°C (968F) |
| Density | 1.527 g/cm³ |
| Crystal structure | Isometric |
| Solubility in water | 29.7g/100g @ 0°C |
| Critical relative humidity | 77.2% @ 30°C |
| Thermochemistry | |
| ΔfH0gas | kJ/mol |
| ΔfH0liquid | kJ/mol |
| ΔfH0solid | -314.55 kJ/mol |
| S0gas, 1 bar | J/mol·K |
| S0liquid, 1 bar | J/mol·K |
| S0solid | 94.85 J/mol·K |
| Safety | |
| Ingestion | Induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water.Seek medical help |
| Inhalation | Remove from exposure and move victim to fresh air. Seek medical help |
| Skin | Wash off with plenty of soap and water |
| Eyes | Flush eyes with plenty of clean water. Seek medical help. |
| NFPA 704 | |
| More info | Hazardous Chemical Database |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references | |
Ammonium chloride or Sal Ammoniac (chemically ammonium chloride (NH4Cl); also nushadir salt, zalmiak, sal armagnac, sal armoniac, salmiakki, salmiak and salt armoniack) is, in its pure form, a clear white water-soluble crystalline salt with a biting, slightly sour taste. The aqueous ammonium chloride solution is mildly acidic.
In nature, the substance occurs in volcanic regions, forming on volcanic rocks near fume-releasing vents. The crystals deposit directly from the gaseous state, and tend to be short-lived, as they dissolve easily in water.
It is easy to produce artificially and is often created as a byproduct of other industries.
Contents |
[edit] Uses
Historically it was considered one of the four alchemical "spirits". While the way that it dissociates into two corrosive materials (ammonia and hydrochloric acid) which attack metals convinced some eager alchemists that it might hold the key to converting one metal to another, Arabs used it as a source of ammonia:
- 2NH4Cl + 2CaO → CaCl2 + Ca(OH)2 + 2NH3
It is used in manufacturing ammonium perchlorate (NH4ClO4):
- NaClO4 + NH4Cl → NH4ClO4 + NaCl
It is sold in blocks at hardware stores for use in cleaning the tip of a soldering iron and can also be included in solder as flux.
Other uses include a feed supplement for cattle, in hair shampoo, in textile printing, in the glue that bonds plywood, as an ingredient in nutritive media for yeast, in cleaning products, and as cough medicine. Its expectorant action is caused by irritative action on the bronchial mucosa. This causes the production of excess respiratory tract fluid which presumably is easier to cough up. It is the active ingredient in many antiperspirants, usually used in aerosol antiperspirants.
Ammonium chloride is used in snow treatment, namely on ski slopes at temperatures above 0 °C, to harden the snow and slow its melting. [1]
In several countries sal ammoniac is used to spice up liquorice-type dark candies (Finland's salmiakki and the Netherlands' zoute drop and the Danish "Dracula - salte Lakridsbolcher - med aegte lakridspulver" are popular examples), and as a flavoring for vodkas.
Ammonium Chloride is used in the second step, after Lithium and Ethylamine, of synthesizing trans alkenes from alkynes
[edit] In history
The modern name "ammonium" comes from sal ammoniac. The substance was known as nushadir salt (Arabic and Persian: نشادر) in Arabic-speaking countries and Persia, naosha (Chinese: 硇砂; pinyin: náoshā) in China, nao sadar in India.
[edit] See also
[edit] External links
cs:Salmiak da:Ammoniumklorid de:Ammoniumchlorid it:Cloruro d'ammonio nl:Salmiak ja:塩化アンモニウム no:Salmiakk nn:Ammoniumklorid pl:Chlorek amonu sr:Амонијум хлорид fi:Ammoniumkloridi sv:Ammoniumklorid th:แอมโมเนียมคลอไรด์ zh:氯化铵
