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General |
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| Name | Hydrogen chloride |
| Chemical formula | H Cl |
| Appearance | Colourless liquid |
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Physical |
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| Formula weight | 36.5 amu |
| Melting point | 203.15 K (-70 °C) |
| Boiling point | 382 K (109 °C) |
| Density | 1.2 ×103 kg/ m3 (liquid) |
| Solubility | 70 g in 100g water |
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Thermochemistry |
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| ΔfH0gasThe standard enthalpy of formation of a compound is the change of enthalpy that accompanies the formation of 1 mole of that substance from its component elements, at their standard states (the most stable form of the element or compound at 25 degrees Cels | -92.31 kJThe joule (symbol J also called newton metre or coulomb volt is the SI unit of energy and work. The unit is pronounced to rhyme with "tool", and is named in honour of the physicist James Prescott Joule (1818-1889). 1 joule 1 N · 1 m 1 newton · 1 metre 1 k/ molThe mole (symbol: mol) is one of the seven SI base units and is commonly used in chemistry. It measures the amount of substance of a system and is defined as the amount of substance that contains as many elementary entities as there are atoms in exactly 0 |
| ΔfH0liquid | ? kJ/mol |
| ΔfH0solid | ? kJ/mol |
| S0gas, 1 barIn chemistry, the standard molar entropy is the entropy content of one mole of substance, under conditions of standard temperature and pressure. By comparing the entropies of products and reactants in a chemical reaction, we can determine whether the reac | 186.9 J/mol·K |
| S0liquid, 1 bar | ? J/mol·K |
| S0solid | ? J/mol·K |
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Safety | |
| Ingestion | Toxic, can be fatal. |
| Inhalation | Fumes may be fatal. Do not give unprotected mouth-to-mouth resuscitation. |
| Skin | May cause severe burns. |
| Eyes | Extremely dangerous. |
| More info | Hazardous Chemical Database |
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SIThe International System of Units (symbol: SI (for the French phrase Systeme International d'Unites , is the most widely used system of units. It is used for everyday commerce in virtually every country of the world except the United States, and it is uni units were used where possible. Unless otherwise stated, standard conditions were used. Disclaimer and references
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The chemical compound hydrochloric acid is a highly acidic aqueous solution of hydrogen chloride ( H Cl). It is highly corrosive and should be handled only with appropriate precautions. Hydrochloric acid is a commonly used chemical reagent and is one of the strong acids that ionize completely in aqueous solution. Concentrated hydrochloric acid has a pH of less than 1.
Hydrochloric acid was discovered around A.D. 800 by Islamic alchemist Jabir Ibn Hayyam (Geber), by distilling common salt ( Na Cl) with sulphuric acid ( H2 SO4). It was known to European alchemists as spirit of salt or acidum salis. Gaseous HCl was called marine acid air. The old (pre- systematic) muriatic acid has the same origin (muriatic means "pertaining to brine or salt"). Hydrochloric acid is still sold under that name at industrial suppliers and hardware stores, for removing mortar stains and film from brickwork, masonry, and stonework.
Aqua regia is a mixture of hydrochloric and nitric acids.Human digestive fluids consist of a mixture of hydrochloric acid and various enzymes which help break down proteins present in food.
Hydrochloric acid is now manufactured by combustion of chlorine gas in hydrogen to make hydrogen chloride gas followed by dissolution of the gas in water.
Hydrochloric acid is generally purchased in a concentrated form and is diluted in a fume cupboard, also kown as a fume hood (see making up solutions).
Unlike other strong acids, hydrochloric acid does not cause rapid damage to healthy skin; it is possible to wash it off before damage occurs.