A general list of deliquescent substances.
Pages in category "Deliquescent substances"
The following 36 pages are in this category, out of 36 total, this list may not reflect recent changes (learn more).
A general list of deliquescent substances.
The following 36 pages are in this category, out of 36 total, this list may not reflect recent changes (learn more).
1. Hygroscopy – Hygroscopy is the phenomenon of attracting and holding water molecules from the surrounding environment, which is usually at normal or room temperature. This is achieved through either absorption or adsorption with the absorbing or adsorbing substance becoming physically changed somewhat. Zinc chloride and calcium chloride, as well as potassium hydroxide and sodium hydroxide, are so hygroscopic that they readily dissolve in the water they absorb, not only is sulfuric acid hygroscopic in concentrated form but its solutions are hygroscopic down to concentrations of 10 Vol-% or below. A hygroscopic material will tend to damp and cakey when exposed to moist air. Because of their affinity for moisture, hygroscopic materials might require storage in sealed containers. When added to foods or other materials for the purpose of maintaining moisture content. Materials and compounds exhibit different hygroscopic properties, and this difference can lead to detrimental effects, differences in hygroscopy can be observed in plastic-laminated paperback book covers—often, in a suddenly moist environment, the book cover will curl away from the rest of the book. The unlaminated side of the cover absorbs more moisture than the side and increases in area. This is similar to the function of a thermostats bi-metallic strip, inexpensive dial-type hygrometers make use of this principle using a coiled strip. Deliquescence, the process by which a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water, deliquescence occurs when the vapour pressure of the solution that is formed is less than the partial pressure of water vapour in the air. While some similar forces are at work here, it is different from capillary attraction, a process where glass or other solid substances attract water, the similar-sounding but unrelated word hydroscopic is sometimes used in error for hygroscopic. A hydroscope is a device used for making observations deep under water. The amount of moisture held by hygroscopic materials is proportional to the relative humidity. Tables containing this information can be found in engineering handbooks and is also available from suppliers of various materials and chemicals. Hygroscopy also plays an important role in the engineering of plastic materials, some plastics are hygroscopic while others are not. The seeds of grasses have hygroscopic extensions that bend with changes in humidity. An example is Needle-and-Thread, Hesperostipa comata, each seed has an awn that twists several turns when the seed is released. Increased moisture causes it to untwist, and, upon drying, to twist again, thorny dragons collect moisture in the dry desert via nighttime condensation of dew that forms on their skin and is channeled to their mouths in hygroscopic grooves between the spines of their skin
2. Aluminium chloride – Aluminium chloride is the main compound of aluminium and chlorine. It is white, but samples are often contaminated with iron chloride, the solid has a low melting and boiling point. It is mainly produced and consumed in the production of aluminium metal, the compound is often cited as a Lewis acid. It is an example of a compound that cracks at mild temperature. AlCl3 adopts three different structures, depending on the temperature and the state, solid AlCl3 is a sheet-like layered cubic close packed layers. In this framework, the Al centres exhibit octahedral coordination geometry, in the melt, aluminium trichloride exists as the dimer Al2Cl6, with tetracoordinate aluminium. This change in structure is related to the density of the liquid phase vs solid aluminium trichloride. Al2Cl6 dimers are also found in the vapour phase, at higher temperatures, the Al2Cl6 dimers dissociate into trigonal planar AlCl3, which is structurally analogous to BF3. The melt conducts electricity poorly, unlike more ionic halides such as sodium chloride, the hexahydrate consists of octahedral 3+ centers and chloride counterions. Hydrogen bonds link the cation and anions, anhydrous aluminium chloride is a powerful Lewis acid, capable of forming Lewis acid-base adducts with even weak Lewis bases such as benzophenone and mesitylene. It forms tetrachloroaluminate AlCl4− in the presence of chloride ions, aluminium chloride reacts with calcium and magnesium hydrides in tetrahydrofuran forming tetrahydroaluminates. Aluminium chloride is hygroscopic, having a very pronounced affinity for water and it fumes in moist air and hisses when mixed with liquid water as the Cl− ions are displaced with H2O molecules in the lattice to form the hexahydrate Cl3. Such solutions are found to be acidic, indicative of partial hydrolysis of the Al3+ ion. 2 Al +3 Cl2 →2 AlCl32 Al +6 HCl →2 AlCl3 +3 H2 Aluminum chloride may be formed via a single displacement reaction between copper chloride and aluminum metal. 2 Al +3 CuCl2 →2 AlCl3 +3 Cu In the US in 1993, approximately 21,000 tons were produced, hydrated aluminium trichloride is prepared by dissolving aluminium oxides in hydrochloric acid. Metallic aluminum also readily dissolves in hydrochloric acid ─ releasing hydrogen gas, AlCl3 is probably the most commonly used Lewis acid and also one of the most powerful. It finds application in the industry as a catalyst for Friedel–Crafts reactions. Important products are detergents and ethylbenzene and it also finds use in polymerization and isomerization reactions of hydrocarbons
3. Aluminium nitrate – Aluminium nitrate is a white, water-soluble salt of aluminium and nitric acid, most commonly existing as the crystalline hydrate, aluminium nitrate nonahydrate, Al3·9H2O. Aluminium nitrate cannot be synthesized by the reaction of aluminium with concentrated nitric acid, Aluminium nitrate may instead be prepared by the reaction of nitric acid with aluminium chloride. Nitrosyl chloride is produced as a by-product, it out of the solution as a gas. Aluminium nitrate may also be prepared a reaction between aluminium sulfate and a nitrate salt with a suitable cation such as barium, strontium, calcium, silver. E. g. Al23 + 3Ba2 → 2Al3 + 3BaSO4 Aluminium nitrate is an oxidizing agent. It is used in tanning leather, antiperspirants, corrosion inhibitors, extraction of uranium, petroleum refining, the nonahydrate and other hydrated aluminium nitrates have many applications. These salts are used to produce alumina for preparation of insulating papers, in cathode ray tube heating elements, the hydrated salts are also used for the extraction of actinide elements. It is used in the laboratory and classroom such as in the reaction, Al3 +3 NaOH → Al3 +3 NaNO3 MSDS of nonahydrate Government of Canada Fact Sheets and Frequently Asked Questions, Aluminum Salts
4. Ammonium bifluoride – Ammonium hydrogen fluoride is the inorganic compound with the formula NH4HF2 or NH4F·HF. It is produced from ammonia and hydrogen fluoride and this colourless salt is a glass-etchant and an intermediate in a once-contemplated route to hydrofluoric acid. Ammonium bifluoride, as its name indicates, contains an ammonium cation, the centrosymmetric triatomic bifluoride anion features the strongest known hydrogen bond, with a F−H length of 114 pm. and a bond energy greater than 155 kJ mol−1. Solutions contain tetrahedral + cations and linear − anions, ammonium bifluoride is a component of some etchants. It attacks silica component of glass, SiO2 +4 → SiF4 +4 F +2 H2O Potassium bifluoride is a more commonly used etchant. Ammonium bifluoride has been considered as an intermediate in the production of acid from hexafluorosilicic acid
5. Cadmium nitrate – Cadmium nitrate describes any of the related members of a family of inorganic compound with the general formula Cd2. xH2O. The anhydrous form is volatile but the others are salts, all are colourless crystalline solids that absorb moisture from air and becomes watery, that is deliquescent. Cadmium compounds are known to be carcinogenic. Cadmium nitrate is used for coloring glass and porcelain and as a powder in photography. When hydrogen sulfide is passed through a solution of cadmium nitrate. A red modification of the sulfide is formed under boiling conditions, when with caustic soda solution, cadmium oxide forms precipitate of cadmium hydroxide. Many insoluble cadmium salts are obtained by such precipitation reactions
6. Calcium chloride – Calcium chloride is an inorganic compound, a salt with the chemical formula CaCl2. It is a crystalline solid at room temperature, highly soluble in water. Calcium chloride is commonly encountered as a solid with generic formula CaCl2x, where x =0,1,2,4. These compounds are used for deicing and dust control. Because the anhydrous salt is hygroscopic, it is used as a desiccant, by depressing the freezing point of water, calcium chloride is used to prevent ice formation and is used to deice. This application consumes the greatest amount of calcium chloride, Calcium chloride is relatively harmless to plants and soil. As a deicing agent, it is effective at lower temperatures than sodium chloride. When distributed for use, it usually takes the form of small, white spheres a few millimeters in diameter. Solutions of calcium chloride can prevent freezing at temperature as low as −52 °C, making it ideal for filling agricultural implement tires as a liquid ballast, also used in salt/chemical-based dehumidifiers in domestic and other environments to adsorb dampness/moisture from the air. The second largest application of calcium chloride exploits its hygroscopic properties, a concentrated solution keeps a liquid layer on the surface of dirt roads, which suppresses formation of dust. It keeps the finer dust particles on the road, providing a cushioning layer, if these are allowed to blow away, the larger aggregate begins to shift around and the road breaks down. Using calcium chloride reduces the need for grading by as much as 50% and this process reduces the erosion of the concrete in the pool. By Le Chateliers principle and the common ion effect, increasing the concentration of calcium in the water will reduce the dissolution of calcium compounds essential to the structure of concrete. As an ingredient, it is listed as a food additive in the European Union for use as a sequestrant. It is considered as generally recognized as safe by the U. S. Food and its use in organic crop production is generally prohibited under US National Organic Programs National List of Allowed and Prohibited Substances. The average intake of calcium chloride as food additives has been estimated to be 160–345 mg/day for individuals, in marine aquariums, calcium chloride is added to introduce bioavailable calcium for calcium carbonate-shelled animals such as mollusks and some cnidarians. Calcium hydroxide or a calcium reactor can also be used to introduce calcium, however, as a firming agent, calcium chloride is used in canned vegetables, in firming soybean curds into tofu and in producing a caviar substitute from vegetable or fruit juices. It is commonly used as an electrolyte in sports drinks and other beverages, the extremely salty taste of calcium chloride is used to flavor pickles while not increasing the foods sodium content
7. Calcium iodide – Calcium iodide is the ionic compound of calcium and iodine. This colourless deliquescent solid is a salt that is soluble in water. Its properties are similar to those for related salts, such as calcium chloride and it is also used in cat food as a source of iodine. 2 CaI2 +2 CO2 + O2 →2 CaCO3 +2 I2
8. Cobalt(II) chloride – Cobalt chloride is an inorganic compound of cobalt and chlorine, with the formula CoCl2. It is usually supplied as the hexahydrate CoCl2·6H2O, which is one of the most commonly used cobalt compounds in the lab, the hexahydrate is purple, whereas the anhydrous form is sky blue. Because of the ease of the reaction, and the resulting color change. Niche uses of cobalt chloride include its role in organic synthesis, Cobalt chloride has been classified as a substance of very high concern by the European Chemicals Agency as it is a suspected carcinogen. Aqueous solutions of both CoCl2 and the contain the species 2+. In the solid state CoCl2·6H2O consists of the molecule trans- and two molecules of water of crystallization and this species dissolves readily in water and alcohol. Concentrated aqueous solutions are red at room temperature but become blue at higher temperatures, CoCl2·6H2O is deliquescent, and the anhydrous salt CoCl2 is hygroscopic, readily converting to the hydrate. Hydrated cobalt chloride is prepared from cobalt hydroxide or cobalt carbonate and hydrochloric acid, CoCO3 +2 HCl +5 H2O → Co6Cl2 + CO2 Upon heating, the hexahydrate dehydrates. Generally, aqueous solutions of cobalt chlorides behave like other cobalt salts since these solutions consist of the 2+ ion regardless of the anion, such solutions give a precipitate of CoS upon treatment with H2S. CoCl2·6H2O and CoCl2 are weak Lewis acids, the adducts are usually either octahedral or tetrahedral. In the laboratory, cobalt chloride serves as a precursor to other cobalt compounds. Reaction of the compound with sodium cyclopentadienide gives cobaltocene. This 19-electron species is a reducing agent, being readily oxidised to the yellow 18-electron cobaltacenium cation. In the presence of ammonia or amines, cobalt is readily oxidised by oxygen to give a variety of cobalt complexes. Other highly basic ligands including carbonate, acetylacetonate, and oxalate induce the formation of Co derivatives, simple carboxylates and halides do not. Unlike Co complexes, Co complexes are very slow to exchange ligands, the existence of cobalt chloride, CoCl3, is disputed, although this compound is listed in some compendia. According to Greenwood and Earnshaw, the only stable binary compounds of cobalt, stated differently, CoCl2 is unreactive toward Cl2. The stability of Co in solution is increased in the presence of ligands of greater Lewis basicity than chloride
9. Gold(III) chloride – Gold chloride, traditionally called auric chloride, is a chemical compound of gold and chlorine. With the molecular formula Au2Cl6, the name gold trichloride is a simplification, referring to the empirical formula, the Roman numerals in the name indicate that the gold has an oxidation state of +3, which is common for gold compounds. There is also another related chloride of gold, gold chloride, chloroauric acid, HAuCl4, the product formed when gold dissolves in aqua regia, is sometimes referred to as gold chloride or acid gold trichloride. Gold chloride is hygroscopic and highly soluble in water as well as ethanol. It decomposes above 160 °C or in light, AuCl3 exists as a chloride-bridged dimer both as a solid and as a vapour, at least at low temperatures. The structure is similar to that of iodine chloride, in gold chloride, each gold center is square planar, which is typical of a metal complex with a d8 electron count. The bonding in AuCl3 is considered somewhat covalent and its acid, chloroauric acid, is then heated to eliminate hydrogen chloride gas. It may be reduced by Fe2+ causing elemental gold to be precipitated from solution, anhydrous AuCl3 begins to decompose to AuCl at around 160 °C, however, this in turn undergoes disproportionation at higher temperatures to give gold metal and AuCl3. AuCl3 → AuCl + Cl23 AuCl → AuCl3 +2 Au AuCl3 is Lewis acidic and readily forms complexes. For example, it reacts with acid to form chloroauric acid, HCl + AuCl 3 → H+ + − Other chloride sources, such as KCl. Aqueous solutions of AuCl3 react with aqueous base such as sodium hydroxide to form a precipitate of Au3, if gently heated, Au3 decomposes to gold oxide, Au2O3, and then to gold metal. Gold chloride is the point for the synthesis of many other gold compounds. Gold salts, especially Na, provide an alternative to mercury salts as catalysts for reactions involving alkynes, an illustrative reaction is the hydration of terminal alkynes to produce methylketones, Some alkynes undergo amination in the presence of gold catalysts. Gold catalyses the alkylation of aromatic rings and a conversion of furans to phenols. In some cases where alkynes are present, phenols sometimes form, as a stoichiometric reagent, auric chloride reacts with benzene under extremely mild conditions to afford the dimeric phenylgold dichloride, PhH + ½Au2Cl6 → ½2 + HCl
10. Iron(III) chloride – Iron chloride, also called ferric chloride, is an industrial scale commodity chemical compound, with the formula FeCl3 and with iron in the +3 oxidation state. The colour of iron chloride crystals depends on the angle, by reflected light the crystals appear dark green. Anhydrous iron chloride is deliquescent, forming hydrated hydrogen chloride mists in moist air and it is rarely observed in its natural form, the mineral molysite, known mainly from some fumaroles. When dissolved in water, iron chloride undergoes hydrolysis and gives off heat in an exothermic reaction, the resulting brown, acidic, and corrosive solution is used as a flocculant in sewage treatment and drinking water production, and as an etchant for copper-based metals in printed circuit boards. Anhydrous iron chloride is a fairly strong Lewis acid, and it is used as a catalyst in organic synthesis, the descriptor hydrated or anhydrous is used when referring to iron chloride, to distinguish between the two common forms. The hexahydrate is usually given as the empirical formula FeCl3⋅6H2O. It may also be given as trans-Cl⋅2H2O and the systematic name tetraaquadichloroiron chloride dihydrate, anhydrous iron chloride adopts the BiI3 structure, which features octahedral Fe centres interconnected by two-coordinate chloride ligands. Iron chloride hexahydrate consists of trans-+ cationic complexes and chloride anions, Iron chloride has a relatively low melting point and boils at around 315 °C. Anhydrous iron chloride may be prepared by union of the elements,2 Fe +3 Cl2 →2 FeCl3 Solutions of iron chloride are produced both from iron and from ore, in a closed-loop process. Conversion of the hydrate to anhydrous iron chloride is not accomplished by heating, as HCl, Iron chloride undergoes hydrolysis to give an acidic solution. When heated with iron oxide at 350 °C, iron chloride gives iron oxychloride, FeCl3 + Fe2O3 →3 FeOCl It is a moderately strong Lewis acid, forming adducts with Lewis bases such as triphenylphosphine oxide, e. g. FeCl32 where Ph = phenyl. It also reacts with other salts to give the yellow tetrahedral FeCl4− ion. Salts of FeCl4− in hydrochloric acid can be extracted into diethyl ether, alkali metal alkoxides react to give the metal alkoxide complexes of varying complexity. The compounds can be dimeric or trimeric, other carboxylate salts form complexes, e. g. citrate and tartrate. Iron chloride is a mild oxidising agent, for example, it is capable of oxidising copper chloride to copper chloride. FeCl3 + CuCl → FeCl2 + CuCl2 It also reacts with iron to iron chloride,2 FeCl3 + Fe →3 FeCl2 Reducing agents such as hydrazine convert iron chloride to complexes of iron. Iron chloride is used in treatment and drinking water production. In this application, FeCl3 in slightly basic water reacts with the ion to form a floc of iron hydroxide, or more precisely formulated as FeO−
11. Iron(III) nitrate – Iron nitrate, or ferric nitrate, is the chemical compound with the formula Fe3. Since it is deliquescent, it is found in its nonahydrate form Fe3·9H2O in which it forms colourless to pale violet crystals. The compound is prepared by treating iron metal powder with nitric acid, fe +4 HNO3 → Fe3 + NO +2 H2O. For example, ferric nitrate on Montmorillonite—a reagent called Clayfen—has been employed for the oxidation of alcohols to aldehydes, ferric nitrate solutions are used by jewelers and metalsmiths to etch silver and silver alloys
12. Lithium iodide – Lithium iodide, or LiI, is a compound of lithium and iodine. When exposed to air, it becomes yellow in color, due to the oxidation of iodide to iodine and it crystallizes in the NaCl motif. It can participate in various hydrates, Lithium iodide is used as an electrolyte for high temperature batteries. It is also used for long life batteries as required, for example, the solid is used as a phosphor for neutron detection. It is also used, in a complex with Iodine, in the electrolyte of dye-sensitized solar cells, in organic synthesis, LiI is useful for cleaving C-O bonds. For example, it can be used to convert methyl esters to carboxylic acids, Lithium iodide was used as a radio contrast agent for X-ray computed tomography imaging studies. Its use was discontinued due to toxicity, replaced by organic iodine molecules. Inorganic iodine solutions suffered from hyperosmolarity and high viscosities, Lithium battery Webelements – Lithium Iodide. --> Composition of LITHIUM IODIDE – NIST
13. Lithium nitrate – Lithium nitrate is an inorganic compound with the formula LiNO3. It is the salt of nitric acid. It is made by reacting lithium carbonate or lithium hydroxide with nitric acid and this deliquescent colourless salt is an oxidizing agent used in the manufacture of red-colored fireworks and flares. Lithium Nitrate has been proposed as a medium to store heat collected from the sun for cooking, a Fresnel lens would be used to melt solid lithium nitrate, which would then function as a solar battery, allowing heat to be redistributed later by convection. LiNO3 is utilized in solute-solvent interactions at decreasing temperatures which in effect, currently, lithium nitrate is being tested to see if it can be applied to concrete-pavement to withstand weathering effects. In the lab, LiNO3 is commonly bound to an ion in order to test bifurcated hydrogen bonds within crystal structures of molecules which can correlate to hydrogen bond strength. Lithium nitrate is used as a catalyst which accelerates the breakdown of nitrogen oxides, through oxidation. Lithium nitrate can be synthesized by reacting nitric acid and lithium carbonate, li2CO3 +2 HNO3 →2 LiNO3 + H2O + CO2 Generally when forming LiNO3, a pH indicator is used to determine when all of the acid has been neutralized. However, this neutralization can also be recognized with the loss of carbon dioxide production, in order to rid the final product of excess water, the sample is heated. Upon thermal decomposition, LiNO3 gives lithium oxide, nitrogen dioxide, because of its relatively small size, the lithium cation is very polarizing, which favors the formation of the oxide. Lithium nitrate is also a good oxidizing agent. Lithium nitrate can be toxic to the body when ingested by targeting the nervous system, thyroids, kidneys. When exposed to the skin, eyes, and mucous membranes, lithium nitrate can cause irritation to these areas
14. Lye – A lye is a liquid metal hydroxide obtained by leaching ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions. Lye is commonly an alternative name of sodium hydroxide or historically potassium hydroxide, today, lye is commercially manufactured using a membrane cell chloralkali process. It is one of the industrial chemicals with worldwide annual production of 45 million tons in 1998. It is supplied in various such as flakes, pellets, microbeads. In the United States, food-grade lye must meet the requirements outlined in the Food Chemicals Codex, as prescribed by the U. S. Food, lower grades of lye which are unsuitable for use in food preparation are commonly used as drain de-cloggers and oven cleaners. Lye in the form of sodium hydroxide and potassium hydroxide is used in making soap. Sodium hydroxide is used to make solid soap, while potassium hydroxide is used to make liquid soap. Potassium hydroxide soaps are softer and more easily dissolved in water than sodium hydroxide soaps, sodium hydroxide and potassium hydroxide are not interchangeable in either the proportions required or the properties produced in making soaps. The cold process method is used to make soap from lye. The lye is mixed with water, and then base oils, butters, the gradual chemical reaction between the lye and the fats eventually produces a solid soap. Hot process soap making also uses lye as the main ingredient, lye is added to water, cooled for a few minutes and then added to oils and butters. The lye is then cooked over a period of time, typically in a slow cooker and this method is much quicker than cold process, as it takes several weeks to complete. The ancient use of lye for soap-making and as a detergent is the origin of the English word, deriving from Proto-Germanic *laugo and ultimately from the Proto-Indo-European root *leue-, to wash. Relatives in other Germanic languages, besides their words for lye, include the Scandinavian languages words for Saturday, lyes are also valued for their cleaning effects. Sodium hydroxide is commonly the major constituent in commercial and industrial cleaners and clogged drain openers. Lyes decompose greases via alkaline ester hydrolysis, yielding water-soluble residues that are removed by rinsing. Sodium or potassium hydroxide can be used to digest tissues of animal carcasses or deceased humans, sodium hydroxide is frequently used in the process of decomposing roadkill dumped in landfills by animal disposal contractors. Due to its low cost and availability, it has used to dispose of corpses by criminals
15. Magnesium chloride – Magnesium chloride is the name for the chemical compound with the formula MgCl2 and its various hydrates MgCl2x. These salts are typical ionic halides, being highly soluble in water, the hydrated magnesium chloride can be extracted from brine or sea water. In North America, magnesium chloride is produced primarily from Great Salt Lake brine and it is extracted in a similar process from the Dead Sea in the Jordan valley. Magnesium chloride, as the natural mineral bischofite, is extracted out of ancient seabeds, for example. Some magnesium chloride is made from solar evaporation of seawater, anhydrous magnesium chloride is the principal precursor to magnesium metal, which is produced on a large scale. Hydrated magnesium chloride is the form most readily available, MgCl2 crystallizes in the cadmium chloride motif, which features octahedral Mg. A variety of hydrates are known with the formula MgCl2x, and each loses water with increasing temperature, in the hexahydrate, the Mg2+ remains octahedral, but is coordinated to six water ligands. The thermal dehydration of the hydrates MgCl2x does not occur straightforwardly, as suggested by the existence of some hydrates, anhydrous MgCl2 is a Lewis acid, although a very weak one. In most of its derivatives, MgCl2 forms octahedral complexes, derivatives with tetrahedral Mg2+ are less common. Examples include salts of 2MgCl4 and adducts such as MgCl, Magnesium chloride is most commonly used for dust control and road stabilization. Its second-most common use is ice control, mixed with hydrated magnesium oxide, magnesium chloride forms a hard material called Sorel cement. This compound is used in fire extinguishers, obtained by the reaction of magnesium hydroxide. Magnesium chloride also is used in medical and topical applications. It can also be used as an anesthetic for cephalopods, some species of crustaceans. MgCl2 is also utilized in the polymerase chain reaction. The magnesium ion is necessary for both in vivo/vitro DNA synthesis, Magnesium chloride is one of many substances used for dust control, soil stabilization and wind erosion mitigation. When magnesium chloride is applied to roads and bare soil areas, the use of magnesium chloride on roads remains controversial. It reduces foreign sediment in nearby waters, helps prevent stunted crop growth caused by clogged pores in plants
16. Magnesium iodide – Magnesium iodide is the name for the chemical compounds with the formulas MgI2 and its various hydrates MgI2x. These salts are typical ionic halides, being highly soluble in water, magnesium iodide has few commercial uses but can be used to prepare compounds for organic synthesis. When heated in air, it completely to magnesium oxide. Another method to prepare MgI2 is mixing powdered elemental iodine and magnesium metal, in order to obtain anhydrous MgI2 the reaction should be conduct in a strictly anhydrous atmosphere and dry-diethyl ether can be used as a solvent. Usage of magnesium iodide in the Baylis-Hillman reaction tends to give -vinyl compounds
17. Manganese(II) sulfate – Manganese sulfate usually refers to the inorganic compound with the formula MnSO4·H2O. This pale pink deliquescent solid is a commercially significant manganese salt, approximately 260 thousand tonnes of manganese sulfate were produced worldwide in 2005. It is the precursor to metal and many other chemical compounds. Mn-deficient soil is remediated with this salt, like many metal sulfates, manganese sulfate forms a variety of hydrates, monohydrate, tetrahydrate, pentahydrate, and heptahydrate. All of these salts dissolve to give faintly pink solutions of the aquo complex 2+, the pale pink colour of Mn salts is highly characteristic. Typically, manganese ores are purified by their conversion to manganese sulfate, treatment of aqueous solutions of the sulfate with sodium carbonate leads to precipitation of manganese carbonate, which can be calcined to give the oxides MnOx. Manganese sulfate is a by-product of various industrially significant oxidations that use manganese dioxide, including the manufacture of hydroquinone, electrolysis of manganese sulfate yields manganese dioxide, which is called EMD for electrolytic manganese dioxide. Alternatively oxidation of manganese sulfate with potassium permanganate yields the so-called chemical manganese dioxide and these materials, especially EMD, are used in dry-cell batteries
18. Mesoxalic acid – Mesoxalic acid, also called oxomalonic acid or ketomalonic acid, is an organic compound with formula C3H2O5 or HO-3-OH. Mesoxalic acid is both an acid and a ketonic acid. It readily loses two protons to yield the divalent anion C3O52−, called mesoxalate, oxomalonate, or ketomalonate. These terms are used for salts containing this anion, such as sodium mesoxalate, Na2C3O5. Mesoxalate is one of the anions, which consist solely of carbon. Mesoxalic acid readily absorbs and reacts with water to form a product commonly called mesoxalic acid hydrate, more properly dihydroxymalonic acid, in product catalogs and other contexts, the terms mesoxalic acid, oxomalonic acid, etc. often refer to this hydrated compound. In particular, the product traded as sodium mesoxalate monohydrate is almost always sodium dihydroxymalonate, the product can be obtained also by oxidation of tartronic acid or glycerol. Since they are carried out in water, these procedures generally give the dihydroxy derivative and it is also prepared by the oxidation of glycerol with the help of Bi3
19. Potassium carbonate – Potassium carbonate is a white salt, soluble in water which forms a strongly alkaline solution. It can be made as the product of potassium hydroxides absorbent reaction with carbon dioxide and it is deliquescent, often appearing a damp or wet solid. Potassium carbonate is used in the production of soap and glass, Potassium carbonate is the primary component of potash and the more refined pearl ash or salts of tartar. Historically, pearl ash was created by baking potash in a kiln to remove impurities, the fine, white powder remaining was the pearl ash. The first patent issued by the US Patent Office was awarded to Samuel Hopkins in 1790 for a method of making potash. In late 18th century North America, before the development of baking powder, today, potassium carbonate is prepared commercially by the electrolysis of potassium chloride. The resulting potassium hydroxide is then carbonated using carbon dioxide to form potassium carbonate, 2KOH + CO2 → K2CO3 + H2O for soap, glass, and china production as a mild drying agent where other drying agents, such as calcium chloride and magnesium sulfate, may be incompatible. It is not suitable for acidic compounds, but can be useful for drying an organic phase if one has an amount of acidic impurity. It may also be used to dry some ketones, alcohols, in cuisine, where it has many traditional uses. It is an ingredient in the production of grass jelly, a food consumed in Chinese and Southeast Asian cuisines, as well as Chinese noodles and it is used to tenderize tripe. German gingerbread recipes often use potassium carbonate as a baking agent and it is however important that the right quantities are used to prevent harm, and cooks should not use it without guidance. In the production of powder to balance the pH of natural cocoa beans. As a fire suppressant in extinguishing deep-fat fryers and various other B class-related fires, in condensed aerosol fire suppression, although as the byproduct of potassium nitrate. As an ingredient in welding fluxes, and in the coating on arc-welding rods. as an aid to stability in neurons helping to maintain equilibrium. As an animal feed ingredient to satisfy the requirements of farmed animals such as broiler breeders. A Dictionary of Science, Oxford University Press, New York,2004 International Chemical Safety Card 1588
20. Potassium hydroxide – Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash. Along with sodium hydroxide, this solid is a prototypical strong base. It has many industrial and niche applications, most of which exploit its corrosive nature, an estimated 700,000 to 800,000 tonnes were produced in 2005. Approximately 100 times more NaOH than KOH is produced annually, KOH is noteworthy as the precursor to most soft and liquid soaps as well as numerous potassium-containing chemicals. Potassium hydroxide can be found in form by reacting sodium hydroxide with impure potassium. It is usually sold as translucent pellets, which will become tacky in air because KOH is hygroscopic, consequently, KOH typically contains varying amounts of water. Its dissolution in water is strongly exothermic, concentrated aqueous solutions are sometimes called potassium lyes. Even at high temperatures, solid KOH does not dehydrate readily, potassium hydroxide solutions with concentrations of approximately 0.5 to 2. 0% are irritating when coming into contact with the skin, while concentrations higher than 2% are corrosive. At higher temperatures, solid KOH crystallizes in the NaCl crystal structure, the OH group is either rapidly or randomly disordered so that the OH− group is effectively a spherical anion of radius 1.53 Å. At room temperature, the OH− groups are ordered and the environment about the K+ centers is distorted, with K+—OH− distances ranging from 2.69 to 3.15 Å, depending on the orientation of the OH group. KOH forms a series of crystalline hydrates, namely the monohydrate KOH·H 2O, the dihydrate KOH·2 H 2O, approximately 121 g of KOH will dissolve in 100 mL of water at room temperature compared with 100 g of NaOH in the same volume. Lower molecular weight alcohols such as methanol, ethanol, and propanols are also excellent solvents, because of its high affinity for water, KOH serves as a desiccant in the laboratory. It is often used to dry basic solvents, especially amines and pyridines, like NaOH, KOH exhibits high thermal stability. Because of its stability and relatively low melting point, it is often melt-cast as pellets or rods, forms that have low surface area. KOH is highly basic, forming strongly alkaline solutions in water and other polar solvents and these solutions are capable of deprotonating many acids, even weak ones. In analytical chemistry, titrations using solutions of KOH are used to assay acids, KOH, like NaOH, serves as a source of OH−, a highly nucleophilic anion that attacks polar bonds in both inorganic and organic materials. In perhaps its most well-known reaction, aqueous KOH saponifies esters, KOH + RCO2R → RCO2K + ROH When R is a long chain and this reaction is manifested by the greasy feel that KOH gives when touched — fats on the skin are rapidly converted to soap and glycerol. Molten KOH is used to displace halides and other leaving groups, the reaction is especially useful for aromatic reagents to give the corresponding phenols
21. Silver perchlorate – Silver perchlorate is the chemical compound with the formula AgClO4. This white solid forms a monohydrate and is mildly deliquescent and it is a useful source of the Ag+ ion, although the presence of perchlorate presents risks. It is used as a catalyst in organic chemistry, silver perchlorate is created by heating a mixture of perchloric acid with silver nitrate. Alternatively, it can be prepared by the reaction between barium perchlorate and silver sulfate, or from the reaction of perchloric acid with silver oxide, silver perchlorate is noteworthy for its solubility in aromatic solvents such as benzene and toluene. In these solvents, the silver cation binds to the arene and it is also amazingly soluble in water, up to 500 g per 100 mL of water. Similar to silver nitrate, silver perchlorate is a reagent for replacing halides ligands with perchlorate. The use of perchlorate in chemical synthesis has declined due to concerns about explosiveness of perchlorate salts. Other silver reagents are silver tetrafluoroborate, and the related silver trifluoromethanesulfonate and silver hexafluorophosphate
22. Sodium formate – Sodium formate, HCOONa, is the sodium salt of formic acid, HCOOH. It usually appears as a white deliquescent powder, in the laboratory, sodium formate can be prepared by neutralizing formic acid with sodium carbonate. It can also be obtained by reacting chloroform with a solution of sodium hydroxide. CHCl3 +4 NaOH → HCOONa +3 NaCl +2 H2O or by reacting sodium hydroxide with chloral hydrate, sodium formate may also be created via the haloform reaction between ethanol and sodium hypochlorite in the presence of a base. This procedure is well documented for the preparation of chloroform, sodium formate crystallizes in a monoclinic crystal system with the lattice parameters a =6,19 Å, b =6,72 Å, c =6,49 Å und β =121, 7°. On heating, sodium formate decomposes to form sodium oxalate and hydrogen, sodium formate is slightly water-hazardous and inhibits some species of bacteria but is degraded by others. Sodium formate is used in fabric dyeing and printing processes. It is also used as a agent for strong mineral acids to increase their pH, as a food additive. The urticating hair of stinging nettles contains in addition to formic acid also sodium formate, the high freezing point depression e. g. in comparison to the still frequently used urea effectively prevents the re-icing, even at temperatures below −15 °C. The thawing effect of the solid sodium formate can even be increased by moistening with aqueous potassium formate or potassium acetate solutions, the degradability of sodium formate is particularly advantageous with a chemical oxygen demand of 211 mg O2/g compared with the de-icing agents sodium acetate and urea with. Saturated sodium formate solutions are used as important drilling and stabilizing aids in gas, by mixing the corresponding saturated alkali metal formate solutions any densities between 1,0 and 2,3 g/cm3 can be set. The saturated solutions are biocidal and long-term stable against microbial degradation, diluted, on the other hand, they are fast and completely biodegradable
23. Sodium nitrate – Sodium nitrate is the chemical compound with the formula NaNO3. This alkali metal salt is also known as Peru saltpeter to distinguish it from ordinary saltpeter. The mineral form is known as nitratine, nitratite or soda niter. Sodium nitrate is a solid very soluble in water. It has been mined extensively for these purposes, with time, however, the mining of South American saltpeter became a profitable business. Chile fought against the allies Peru and Bolivia in the War of the Pacific 1879-1884, in 1919, Ralph Walter Graystone Wyckoff determined its crystal structure using X-ray crystallography. The largest accumulations of naturally occurring sodium nitrate are found in Chile and Peru, by the 1940s, this conversion process resulted in a dramatic decline in demand for sodium nitrate procured from natural sources. Chile still has the largest reserves of caliche, with mines in such locations as Pedro de Valdivia, María Elena and Pampa Blanca. Sodium nitrate, potassium nitrate, sodium sulfate and iodine are all obtained by the processing of caliche, the former Chilean saltpeter mining communities of Humberstone and Santa Laura were declared Unesco World Heritage sites in 2005. It can be combined with iron hydroxide to make a synthetic resin, sodium nitrate can be combined with sulfuric acid and nitric acid distilled off. At lower pressure the temperature needed results in less decomposition. The theoretical 2 moles of nitric acid per 1 mole of sulfuric acid results in a high end temperature, much decomposition. When this reaction was important industrially, it was practice to operate with sulfuric acid in excess to end on a mostly bisulfate product poured molten out of the retort. Hobbyist gold refiners use sodium nitrate to make a hybrid aqua regia that dissolves gold, sodium nitrate is also a food additive used as a preservative and color fixative in cured meats and poultry, it is listed under its INS number 251 or E number E251. It is approved for use in the EU, USA and Australia, sodium nitrate should not be confused with sodium nitrite, which is also a common food additive and preservative used, for example, in deli meats. Less common applications include as an oxidizer in fireworks, replacing potassium nitrate commonly found in black powder, sodium nitrate is used together with potassium nitrate and calcium nitrate for heat storage and, more recently, for heat transfer in solar power plants. A mixture of sodium nitrate, calcium nitrate and potassium nitrate is used as material in prototype plants, such as Andasol Solar Power Station. It is also used in the industry for facultative microorganism respiration
24. Taurocholic acid – Taurocholic acid, known also as cholaic acid, cholyltaurine, or acidum cholatauricum, is a deliquescent yellowish crystalline bile acid involved in the emulsification of fats. It occurs as a salt in the bile of mammals. It is a conjugate of cholic acid with taurine, in medical use, it is administered as a cholagogue and choleretic. Hydrolysis of taurocholic acid yields taurine, for commercial use, taurocholic acid is manufactured from cattle bile, a byproduct of the meat-processing industry. This acid is one of the many molecules in the body that has cholesterol as its precursor. The median lethal dose of taurocholic acid in rats is 380 mg/kg
25. Tellurium tetrachloride – Tellurium tetrachloride is the inorganic compound with the empirical formula TeCl4. The compound is volatile, subliming at 200 °C at 0.1 mm Hg, molten TeCl4 is ionic, dissociating into ions TeCl3+ and Te2Cl102−. TeCl4 is monomeric in the gas phase, with a similar to that of SF4. In the solid state, it is a tetrameric cubane-like cluster, the cluster with a Te4Cl4 core and three terminal chloride ligands for each Te. The product is isolated by distillation, TeCl4 has proven of occasional interest in organic synthesis. It adds to alkenes to give Cl-C-C-TeCl3 derivatives, wherein the Te can be removed with sodium sulfide. Electron-rich arenes react to give aryl Te compounds, thus anisole give TeCl22, which can be reduced to the diaryl telluride. As is the case for other compounds, TeCl4 is toxic. It also releases HCl upon hydrolysis
26. Tetrapropylammonium perruthenate – Tetrapropylammonium perruthenate is the chemical compound described by the formula N4RuO4. Sometimes known as the Ley–Griffith reagent, this compound is used as a reagent in organic synthesis. This salt consists of the cation and the perruthenate, RuO4− anion. Ruthenium tetroxide is an aggressive oxidant, but its one-electron reduced derivative is a mild oxidizing agent for the conversion of alcohols to aldehydes. This oxidizing agent can also be used to oxidize primary alcohols all the way to the carboxylic acid, use of a higher catalyst loading, larger amount of the co-oxidant, and addition of two equivalents of water. In this situation, the aldehyde reacts with water to form the geminal-diol hydrate, the oxidation generates water that can be removed by adding molecular sieves. TPAP is expensive, but it can be used in catalytic amounts, the catalytic cycle is maintained by adding a stoichiometric amount of a co-oxidant such as N-methylmorpholine N-oxide or molecular oxygen
27. Tin(II) chloride – Tin chloride, also known as stannous chloride, is a white crystalline solid with the formula SnCl2. It forms a dihydrate, but aqueous solutions tend to undergo hydrolysis. SnCl2 is widely used as an agent, and in electrolytic baths for tin-plating. Tin chloride should not be confused with the chloride of tin, tin chloride or stannic chloride. SnCl2 has a pair of electrons, such that the molecule in the gas phase is bent. In the solid state, crystalline SnCl2 forms chains linked via chloride bridges as shown, the dihydrate is also three-coordinate, with one water coordinated on to the tin, and a second water coordinated to the first. The main part of the molecule stacks into double layers in the crystal lattice, with the second water sandwiched between the layers. Solutions of SnCl2 are also unstable towards oxidation by the air,6 SnCl2 + O2 +2 H2O →2 SnCl4 +4 SnCl This can be prevented by storing the solution over lumps of tin metal. Solutions of tin chloride can also simply as a source of Sn2+ ions. For example, the salt of 4-methyl-2, 6-di-tert-butylphenol reacts with SnCl2 in THF to give the yellow linear two-coordinate compound Sn2. The lone pair of electrons in such complexes is available for bonding, however and this seen in the ferrocene-related product of the following reaction, SnCl2 + Fe2HgCl → Fe2SnCl3 + Hg SnCl2 can be used to make a variety of such compounds containing metal-metal bonds. For example, the reaction with dicobalt octacarbonyl, SnCl2 + Co28 → 4Co--Co4 Anhydrous SnCl2 is prepared by the action of dry hydrogen chloride gas on tin metal. The dihydrate is made by a reaction, using hydrochloric acid. This dihydrate can be dehydrated to anhydrous using acetic anhydride, a solution of tin chloride containing a little hydrochloric acid is used for the tin-plating of steel, in order to make tin cans. An electric potential is applied, and tin metal is formed at the cathode via electrolysis, tin chloride is used as a mordant in textile dyeing because it gives brighter colours with some dyes e. g. cochineal. This mordant has also used alone to increase the weight of silk. It is used as a catalyst in the production of the plastic polylactic acid and it also finds a use as a catalyst between acetone and hydrogen peroxide to form the tetrameric form of acetone peroxide. Tin chloride also finds use as a reducing agent
28. Yttrium(III) chloride – Yttrium chloride is an inorganic compound of yttrium and chloride. It exists in two forms, the hydrate and an anhydrous form, both are colourless solids that are highly soluble in water, and deliquescent. This structure is shared by a range of compounds notably AlCl3, yCl3 is often prepared by the ammonium chloride route, starting from either Y2O3 or hydrated chloride or oxychloride. Treating Y2O3 with aqueous HCl produces hydrated chloride and this salt cannot be rendered anhydrous by heating
29. Zinc chloride – Zinc chloride is the name of chemical compounds with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, ZnCl2 itself is hygroscopic and even deliquescent. Samples should therefore be protected from sources of moisture, including the water present in ambient air. Zinc chloride finds wide application in textile processing, metallurgical fluxes, no mineral with this chemical composition is known aside from the very rare mineral simonkolleite, Zn58Cl2·H2O. Four crystalline forms of ZnCl2 are known, α, β, γ, and δ, here, a, b, and c are lattice constants, Z is the number of structure units per unit cell and ρ is the density calculated from the structure parameters. Rapid cooling of molten ZnCl2 gives a glass, the covalent character of the anhydrous material is indicated by its relatively low melting point of 275 °C. Further evidence for covalency is provided by the solubility of the dichloride in ethereal solvents where it forms adducts with the formula ZnCl2L2. In the gas phase, ZnCl2 molecules are linear with a length of 205 pm. Molten ZnCl2 has a viscosity at its melting point and a comparatively low electrical conductivity that increases markedly with temperature. A Raman scattering study of the melt indicated the presence of polymeric structures, five hydrates of zinc chloride are known, ZnCl2n where n =1,1.5,2.5,3 and 4. The tetrahydrate ZnCl24 crystallizes from solutions of zinc chloride. Anhydrous ZnCl2 can be prepared from zinc and hydrogen chloride, Zn +2 HCl → ZnCl2 + H2 Hydrated forms and aqueous solutions may be readily prepared similarly by treating Zn metal with hydrochloric acid. Commercial samples of zinc chloride typically contain water and products from hydrolysis as impurities, such samples may be purified by recrystallization from hot dioxane. Anhydrous samples can be purified by sublimation in a stream of hydrogen chloride gas, finally, the simplest method relies on treating the zinc chloride with thionyl chloride. Molten anhydrous ZnCl2 at 500–700 °C dissolves zinc metal, and, on cooling of the melt, a yellow diamagnetic glass is formed. A number of containing the tetrachlorozincate anion, ZnCl2−4, are known. Caultons reagent, V2Cl36Zn2Cl6 is an example of a salt containing Zn2Cl2−6, the compound Cs3ZnCl5 contains tetrahedral ZnCl2−4 and Cl− anions. No compounds containing the ZnCl4−6 ion have been characterized, whilst zinc chloride is very soluble in water, solutions cannot be considered to contain simply solvated Zn2+ ions and Cl− ions, ZnClxH2O species are also present