|
Ammonium Iodide
Ammonium iodide is the chemical compound NH4I. It is used in photographic chemicals and some medications.Holleman, A. F.; Wiberg, E. ''Inorganic Chemistry'' Academic Press: San Diego, 2001. . It can be prepared by the action of hydroiodic acid on ammonia. It is easily soluble in water, from which it crystallizes in cubes. It is also soluble in ethanol. It gradually turns yellow on standing in moist air, owing to decomposition with liberation of iodine. Preparation Ammonium iodide can be made in lab by reacting ammonia or ammonium hydroxide with hydroiodic acid or hydrogen iodide gas: : NH3 + HI → NH4I : NH4OH + HI → NH4I + H2O It is also formed by the decomposition of ammoniated nitrogen triiodide Nitrogen triiodide is an inorganic compound with the formula N I3. It is an extremely sensitive contact explosive: small quantities explode with a loud, sharp snap when touched even lightly, releasing a purple cloud of iodine vapor; it can even b ... (an explosive). Referenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sublimation (physics)
Sublimation is the Phase transition, transition of a substance directly from the solid to the gas state, without passing through the liquid state. Sublimation is an endothermic process that occurs at temperatures and pressures below a substance's triple point in its phase diagram, which corresponds to the lowest pressure at which the substance can exist as a liquid. The reverse process of sublimation is deposition (phase transition), deposition or desublimation, in which a substance passes directly from a gas to a solid phase. Sublimation has also been used as a generic term to describe a solid-to-gas transition (sublimation) followed by a gas-to-solid transition (deposition (phase transition), deposition). While vaporization from liquid to gas occurs as evaporation from the surface if it occurs below the boiling point of the liquid, and as boiling with formation of bubbles in the interior of the liquid if it occurs at the boiling point, there is no such distinction for the solid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to 45% of the world's food and fertilizers. Around 70% of ammonia is used to make fertilisers in various forms and composition, such as urea and Diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products. It is mainly collected by downward displacement of both air and water. Although common in nature—both terrestrially and in the outer planets of the Solar System—and in wide use, ammonia is both caust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodides
An iodide ion is the ion I−. Compounds with iodine in formal oxidation state −1 are called iodides. In everyday life, iodide is most commonly encountered as a component of iodized salt, which many governments mandate. Worldwide, iodine deficiency affects two billion people and is the leading preventable cause of intellectual disability. Structure and characteristics of inorganic iodides Iodide is one of the largest monatomic anions. It is assigned a radius of around 206 picometers. For comparison, the lighter halides are considerably smaller: bromide (196 pm), chloride (181 pm), and fluoride (133 pm). In part because of its size, iodide forms relatively weak bonds with most elements. Most iodide salts are soluble in water, but often less so than the related chlorides and bromides. Iodide, being large, is less hydrophilic compared to the smaller anions. One consequence of this is that sodium iodide is highly soluble in acetone, whereas sodium chloride is not. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Triiodide
Nitrogen triiodide is an inorganic compound with the formula N I3. It is an extremely sensitive contact explosive: small quantities explode with a loud, sharp snap when touched even lightly, releasing a purple cloud of iodine vapor; it can even be detonated by alpha radiation. NI3 has a complex structural chemistry that is difficult to study because of the instability of the derivatives. Although nitrogen is more electronegative than iodine, the compound was so named due to its analogy to the compound nitrogen trichloride. Structure of NI3 and its derivatives Nitrogen triiodide was first characterized by Raman spectroscopy in 1990 when it was prepared by an ammonia-free route. Boron nitride reacts with iodine monofluoride in trichlorofluoromethane at −30 °C to produce pure NI3 in low yield: :BN + 3 IF → NI3 + BF3 NI3 is pyramidal (C3v molecular symmetry), as are the other nitrogen trihalides and ammonia. The material that is usually called "nitrogen triiodide" is pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent). It is vital for all known forms of life, despite not providing food, energy or organic micronutrients. Its chemical formula, H2O, indicates that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. The hydrogen atoms are attached to the oxygen atom at an angle of 104.45°. "Water" is also the name of the liquid state of H2O at standard temperature and pressure. A number of natural states of water exist. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds consist of suspended droplets of water and ice, its solid state. When finely divided, crystalline ice may precipitate in the form of snow. The gaseous state of water is steam or water vapor. Water co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Hydroxide
Ammonia solution, also known as ammonia water, ammonium hydroxide, ammoniacal liquor, ammonia liquor, aqua ammonia, aqueous ammonia, or (inaccurately) ammonia, is a solution of ammonia in water. It can be denoted by the symbols NH3(aq). Although the name ammonium hydroxide suggests an alkali with chemical formula, composition , it is actually impossible to isolate samples of NH4OH. The ions and OH− do not account for a significant fraction of the total amount of ammonia except in extremely dilute solutions. Basicity of ammonia in water In aqueous solution, ammonia deprotonation, deprotonates a small fraction of the water to give ammonium and hydroxide according to the following chemical equilibrium, equilibrium: : NH3 + H2O NH4+ + OH−. In a 1 Molar concentration, M ammonia solution, about 0.42% of the ammonia is converted to ammonium, equivalent to pH = 11.63 because [NH4+] = 0.0042 M, [OH−] = 0.0042 M, [NH3] = 0.9958 M, and pH = 14 + log10[OHâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Iodide
Hydrogen iodide () is a diatomic molecule and hydrogen halide. Aqueous solutions of HI are known as hydroiodic acid or hydriodic acid, a strong acid. Hydrogen iodide and hydroiodic acid are, however, different in that the former is a gas under standard conditions, whereas the other is an aqueous solution of the gas. They are interconvertible. HI is used in organic and inorganic synthesis as one of the primary sources of iodine and as a reducing agent. Properties of hydrogen iodide HI is a colorless gas that reacts with oxygen to give water and iodine. With moist air, HI gives a mist (or fumes) of hydroiodic acid. It is exceptionally soluble in water, giving hydroiodic acid. One liter of water will dissolve 425 liters of HI gas, the most concentrated solution having only four water molecules per molecule of HI. Hydroiodic acid Hydroiodic acid is not pure hydrogen iodide, but a mixture containing it. Commercial "concentrated" hydroiodic acid usually contains 48–57% HI by mass. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek 'violet-coloured'. Iodine occurs in many oxidation states, including iodide (I−), iodate (), and the various periodate anions. It is the least abundant of the stable halogens, being the sixty-first most abundant element. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities. The dominant producers of iodine today are Chile and Japan. Due to its high atomic number and ease of attachment to organic compound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a Volatility (chemistry), volatile, Combustibility and flammability, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of Carbohydrate, sugars by yeasts or via Petrochemistry, petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the Chemical synthesis, synthesis of organic compounds, and as a Alcohol fuel, fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water (molecule)
Water () is a Chemical polarity, polar inorganic compound that is at room temperature a tasteless and odorless liquid, which is nearly colorless apart from Color of water, an inherent hint of blue. It is by far the most studied chemical compound and is described as the "universal solvent" and the "solvent of life". It is the most abundant substance on the surface of Earth and the only common substance to exist as a ice, solid, liquid, and water vapor, gas on Earth's surface. It is also the third most abundant molecule in the universe (behind Hydrogen, molecular hydrogen and carbon monoxide). Water molecules form hydrogen bonds with each other and are strongly polar. This polarity allows it to dissociate ions in salts and bond to other polar substances such as alcohols and acids, thus dissolving them. Its hydrogen bonding causes its many unique properties, such as having a solid form less dense than its liquid form, a relatively high boiling point of 100 °C for its molar m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroiodic Acid
Hydroiodic acid (or hydriodic acid) is an aqueous solution of hydrogen iodide (HI). It is a strong acid, one that is ionized completely in an aqueous solution. It is colorless. Concentrated solutions are usually 48% to 57% HI. Reactions Hydroiodic acid reacts with oxygen in air to give iodine: :4 HI + O2 → 2 + 2 I2 Like other hydrogen halides, hydroiodic acid adds to alkenes to give alkyl iodides. It can also be used as a reducing agent, for example in the reduction of aromatic nitro compounds to anilines. Cativa process The Cativa process is a major end use of hydroiodic acid, which serves as a co-catalyst for the production of acetic acid by the carbonylation of methanol. Illicit uses Hydroiodic acid is listed as a U.S. Federal DEA List I Chemical, owing to its use as a reducing agent related to the production of methamphetamine from ephedrine Ephedrine is a central nervous system (CNS) stimulant that is often used to prevent low blood pressure during anesthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Fluoride
Ammonium fluoride is the inorganic compound with the formula NH4F. It crystallizes as small colourless prisms, having a sharp saline taste, and is highly soluble in water. Like all fluoride salts, it is moderately toxic in both acute and chronic overdose. Crystal structure Ammonium fluoride adopts the wurtzite crystal structure, in which both the ammonium cations and the fluoride anions are stacked in ABABAB... layers, each being tetrahedrally surrounded by four of the other. There are N−H···F hydrogen bonds between the anions and cations. This structure is very similar to ice, and ammonium fluoride is the only substance which can form mixed crystals with water. Reactions On passing hydrogen fluoride gas (in excess) through the salt, ammonium fluoride absorbs the gas to form the addition compound ammonium bifluoride. The reaction occurring is: :NH4F + HF → NH4HF2 It sublimes when heated—a property common among ammonium salts. In the sublimation, the salt decomposes to am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
-3D-balls.png "Click for more on -> Ammonia")
.svg "Click for more on -> Water")
