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Sulfur
Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with the chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant element by mass in the universe and the fifth most common on Earth. Though sometimes found in pure, native form, sulfur on Earth usually occurs as sulfide and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt. Historically and in literature sulfur is also called brimstone, which means "burning stone". Almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum.. Downloahere Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, and hydrogen, with the molecular formula . It is a colorless, odorless, and Viscosity, viscous liquid that is Miscibility, miscible with water. Pure sulfuric acid does not occur naturally due to its Dehydration reaction, strong affinity to water vapor; it is Hygroscopy, hygroscopic and readily absorbs water vapor from the Atmosphere of Earth, air. Concentrated sulfuric acid is a strong oxidant with powerful dehydrating properties, making it highly corrosive towards other materials, from rocks to metals. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid but, to the contrary, dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is releas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonmetal (chemistry)
In the context of the periodic table, a nonmetal is a chemical element that mostly lacks distinctive metallic properties. They range from colorless gases like hydrogen to shiny crystals like iodine. Physically, they are usually lighter (less dense) than elements that form metals and are often poor conductors of heat and electricity. Chemically, nonmetals have relatively high electronegativity or usually attract electrons in a chemical bond with another element, and their oxides tend to be acidic. Seventeen elements are widely recognized as nonmetals. Additionally, some or all of six borderline elements ( metalloids) are sometimes counted as nonmetals. The two lightest nonmetals, hydrogen and helium, together account for about 98% of the mass of the observable universe. Five nonmetallic elements—hydrogen, carbon, nitrogen, oxygen, and silicon—form the bulk of Earth’s atmosphere, biosphere, crust and oceans, although metallic elements are believed to be slightly more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octasulfur
Octasulfur is an inorganic substance with the chemical formula . It is an odourless and tasteless yellow solid, and is a major industrial chemical. It is the most common allotrope of sulfur Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ... and occurs widely in nature.Steudel, R., "Homocyclic Sulfur Molecules", Topics Curr. Chem. 1982, 102, 149. Nomenclature The name octasulfur is the most commonly used for this chemical. It is systematically named ''cyclo''-octasulfur (which is the preferred IUPAC name) and cyclooctasulfane. It is also the final member of the thiocane heterocylic series, where every carbon atom is substituted with a sulfur atom, thus this sulfur allotrope is systematically named octathiocane as well. Structure The chemical consists of rings of 8 sulfur ato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Spelling
Despite the various list of dialects of English, English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variations being British and American spelling. Many of Comparison of American and British English, the differences between American English, American and British English, British or English in the Commonwealth of Nations, Commonwealth English date back to a time before spelling standards were developed. For instance, some spellings seen as "American" today were once commonly used in Britain, and some spellings seen as "British" were once commonly used in the United States. A "British standard" began to emerge following the 1755 publication of Samuel Johnson's ''A Dictionary of the English Language'', and an "American standard" started following the work of Noah Webster and, in particular, his ''Webster's Dictionary, An American Dictionary of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Match
A match is a tool for starting a fire. Typically, matches are made of small wooden sticks or stiff paper. One end is coated with a material that can be ignited by friction generated by striking the match against a suitable surface. Wooden matches are packaged in matchboxes, and paper matches are partially cut into rows and stapled into matchbooks. The coated end of a match, known as the match "head", consists of a bead of active ingredients and binder (material), binder, often colored for easier inspection. There are two main types of matches: safety matches, which can be struck only against a specially prepared surface, and strike-anywhere matches, for which any suitably frictional surface can be used. Etymology The word ''match'' derives from Old French ''mèche'', referring to the Candle wick, wick of a candle. Historically, the term ''match'' referred to lengths of rope, cord (later cambric) impregnated with chemicals, and allowed to burn continuously. These were used to li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garlic
Garlic (''Allium sativum'') is a species of bulbous flowering plants in the genus '' Allium''. Its close relatives include the onion, shallot, leek, chives, Welsh onion, and Chinese onion. Garlic is native to central and south Asia, stretching from the Black Sea through the southern Caucasus, northeastern Iran, and the Hindu Kush; it also grows wild in parts of Mediterranean Europe. There are two subspecies and hundreds of varieties of garlic. Garlic has been used for thousands of years as a seasoning, culinary ingredient, traditional medical remedy; it was known in many ancient civilizations, including the Babylonians, Egyptians, Romans, and Chinese, and remains significant in many cuisines and folk treatments, especially across the Mediterranean and Asia. Garlic propagates in a variety of climates and conditions and is produced globally; China is by far the largest producer, accounting for over two thirds (73%) of the world's supply in 2021. Description Garli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petroleum
Petroleum, also known as crude oil or simply oil, is a naturally occurring, yellowish-black liquid chemical mixture found in geological formations, consisting mainly of hydrocarbons. The term ''petroleum'' refers both to naturally occurring unprocessed crude oil, as well as to petroleum products that consist of refining, refined crude oil. Petroleum is a fossil fuel formed over millions of years from anaerobic decay of organic materials from buried prehistoric life, prehistoric organisms, particularly planktons and algae, and 70% of the world's oil deposits were formed during the Mesozoic. Conventional reserves of petroleum are primarily recovered by oil drilling, drilling, which is done after a study of the relevant structural geology, sedimentary basin analysis, analysis of the sedimentary basin, and reservoir characterization, characterization of the petroleum reservoir. There are also unconventional (oil & gas) reservoir, unconventional reserves such as oil sands and oil sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Element
A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its atomic nucleus, nucleus. Atoms of the same element can have different numbers of neutrons in their nuclei, known as isotopes of the element. Two or more atoms can combine to form molecules. Some elements form Homonuclear molecule, molecules of atoms of said element only: e.g. atoms of hydrogen (H) form Diatomic molecule, diatomic molecules (H). Chemical compounds are substances made of atoms of different elements; they can have molecular or non-molecular structure. Mixtures are materials containing different chemical substances; that means (in case of molecular substances) that they contain different types of molecules. Atoms of one element can be transformed into atoms of a different element in nuclear reactions, which change an atom's at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bad Breath
Bad breath, also known as halitosis, is a symptom in which a noticeably unpleasant breath odour is present. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder. The concerns of bad breath may be divided into genuine and non-genuine cases. Of those who have genuine bad breath, about 85% of cases come from inside the mouth. The remaining cases are believed to be due to disorders in the nose, sinuses, throat, lungs, esophagus, or stomach. Rarely, bad breath can be due to an underlying medical condition such as liver failure or ketoacidosis. Non-genuine cases occur when someone complains of having bad breath but other people cannot detect it. This is estimated to make up between 5% and 72% of cases. The treatment depends on the underlying cause. Initial efforts may include tongue cleaning, mouthwash, and flossing. Tentative evidence supports the use of mouthwash containing chlorhexidine or cetylpyridi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abundance Of The Chemical Elements
The abundance of the chemical elements is a measure of the Type–token distinction#Occurrences, occurrences of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by mass fraction (chemistry), ''mass fraction'' (in commercial contexts often called ''weight fraction''), by ''mole fraction'' (fraction of atoms by numerical count, or sometimes fraction of molecules in gases), or by ''volume fraction''. Volume fraction is a common abundance measure in mixed gases such as planetary atmospheres, and is similar in value to molecular mole fraction for gas mixtures at relatively low densities and pressures, and ideal gas mixtures. Most abundance values in this article are given as mass fractions. The abundance of chemical elements in the universe is dominated by the large amounts of hydrogen and helium which were produced during Big Bang nucleosynthesis. Remaining elements, making up only about 2% of the universe, were lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertilizer
A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Many sources of fertilizer exist, both natural and industrially produced. For most modern agricultural practices, fertilization focuses on three main macro nutrients: nitrogen (N), phosphorus (P), and potassium (K) with occasional addition of supplements like rock flour for micronutrients. Farmers apply these fertilizers in a variety of ways: through dry or pelletized or liquid application processes, using large agricultural equipment, or hand-tool methods. Historically, fertilization came from natural or organic sources: compost, animal manure, human manure, harvested minerals, crop rotations, and byproducts of human-nature industries (e.g. fish processing waste, or bloodmeal from animal slaughter). However, starting in the 19th cen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Gas
Natural gas (also fossil gas, methane gas, and gas) is a naturally occurring compound of gaseous hydrocarbons, primarily methane (95%), small amounts of higher alkanes, and traces of carbon dioxide and nitrogen, hydrogen sulfide and helium. Methane is a colorless and odorless gas, and, after carbon dioxide, is the second-greatest greenhouse gas that contributes to global climate change. Because natural gas is odorless, a commercial odorizer, such as Methanethiol (mercaptan brand), that smells of hydrogen sulfide (rotten eggs) is added to the gas for the ready detection of gas leaks. Natural gas is a fossil fuel that is formed when layers of organic matter (primarily marine microorganisms) are thermally decomposed under oxygen-free conditions, subjected to intense heat and pressure underground over millions of years. The energy that the decayed organisms originally obtained from the sun via photosynthesis is stored as chemical energy within the molecules of methane and other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
