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White Lead
White lead is the basic lead carbonate 2PbCO3·Pb(OH)2. It is a complex salt, containing both carbonate and hydroxide ions. White lead occurs naturally as a mineral, in which context it is known as hydrocerussite, a hydrate of cerussite. It was formerly used as an ingredient for lead paint and a cosmetic called Venetian ceruse, because of its opacity and the satiny smooth mixture it made with dryable oils. However, it tended to cause lead poisoning, and its use has been banned in most countries. White lead compounds known as lead soap were also used as additive for lubricants for bearings and in machine shops. Lead soap was also used as an oil drying agent for paints made with drying oil or air drying paints made with alkyd resins. Lead is often used with cobalt driers. Lead free substitutes have been developed to replace this use of lead in paint. History What is commonly known today as the "Dutch method" for the preparation of white lead was described as early as Theoph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead(II) Compounds
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, lead is a shiny gray with a hint of blue. It tarnishes to a dull gray color when exposed to air. Lead has the highest atomic number of any stable element and three of its isotopes are endpoints of major nuclear decay chains of heavier elements. Lead is toxic, even in small amounts, especially to children. Lead is a relatively unreactive post-transition metal. Its weak metallic character is illustrated by its amphoteric nature; lead and lead oxides react with acids and bases, and it tends to form covalent bonds. Compounds of lead are usually found in the +2 oxidation state rather than the +4 state common with lighter members of the carbon group. Exceptions are mostly limited to organolead compounds. Like the lighter members of the group, le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead Paint2
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, lead is a shiny gray with a hint of blue. It tarnishes to a dull gray color when exposed to air. Lead has the highest atomic number of any stable element and three of its isotopes are endpoints of major nuclear decay chains of heavier elements. Lead is toxic, even in small amounts, especially to children. Lead is a relatively unreactive post-transition metal. Its weak metallic character is illustrated by its amphoteric nature; lead and lead oxides react with acids and bases, and it tends to form covalent bonds. Compounds of lead are usually found in the +2 oxidation state rather than the +4 state common with lighter members of the carbon group. Exceptions are mostly limited to organolead compounds. Like the lighter members of the group, le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, lead is a shiny gray with a hint of blue. It tarnishes to a dull gray color when exposed to air. Lead has the highest atomic number of any stable element and three of its isotopes are endpoints of major nuclear decay chains of heavier elements. Lead is toxic, even in small amounts, especially to children. Lead is a relatively unreactive post-transition metal. Its weak metallic character is illustrated by its amphoteric nature; lead and lead oxides react with acids and bases, and it tends to form covalent bonds. Compounds of lead are usually found in the +2 oxidation state rather than the +4 state common with lighter members of the carbon group. Exceptions are mostly limited to organolead compounds. Like the lighter members of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. It is a trace gas in Earth's atmosphere at 421 parts per million (ppm), or about 0.04% by volume (as of May 2022), having risen from pre-industrial levels of 280 ppm. Burning fossil fuels is the primary cause of these increased CO2 concentrations and also the primary cause of climate change.IPCC (2022Summary for policy makersiClimate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA Carbon dioxide is soluble in water and is found in groundwater, lakes, ice caps, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Lead (Painting) Convention, 1921
White Lead (Painting) Convention, 1921 is an International Labour Organization Convention established in 1921 to advance the prohibition of using white lead in paint. As of 2017 many leading global nations, including the United States, the United Kingdom, Germany, Japan, China and India remain outside the organization. Ratifications As of 2013, the convention has been ratified by 63 states: References {{Reflist External links TextRatifications Health treaties White White is the lightest color and is achromatic (having no hue). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully reflect and scatter all the visible wavelengths of light. White on ... Occupational safety and health treaties Treaties concluded in 1921 Treaties entered into force in 1923 Lead Treaties of the Kingdom of Afghanistan Treaties of Algeria Treaties of Argentina Treaties of the First Austrian Republic Treaties of Azerbaijan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Inorganic Pigments
The following list includes commercially or artistically important inorganic pigments of natural and synthetic origin.. Purple pigments Aluminum pigments * Ultramarine violet: (PV15) - a synthetic or naturally occurring sulfur containing silicate mineral. Copper pigments *Han purple: BaCuSi2O6. Cobalt pigments *Cobalt violet: (PV14) Co3(PO4)2. Manganese pigments *Manganese violet: NH4MnP2O7 (PV16) manganic ammonium pyrophosphate. Gold pigments *Purple of Cassius: Gold nanoparticles suspended in tin dioxide - Aux • SnO2. Blue pigments Aluminum pigments *Ultramarine (PB29): a synthetic or naturally occurring sulfur containing silicate mineral - (generalized formula) *Persian blue: made by grinding up the mineral Lapis lazuli. The most important mineral component of lapis lazuli is lazurite (25% to 40%), a feldspathoid silicate mineral with the formula . Cobalt pigments *Cobalt blue (PB28): cobalt(II) aluminate. * Cerulean blue (PB35): cobalt(II) stannate. *Cerium ura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teredo Navalis
''Teredo navalis'', commonly called the naval shipworm or turu, is a species of saltwater clam, a marine bivalve mollusc in the family ''Teredinidae''. This species is the type species of the genus '' Teredo''. Like other species in this family, this bivalve is called a shipworm, because it resembles a worm in general appearance, while at the anterior end it has a small shell with two valves which is adept at boring through wood. This species may have originated in the northeast Atlantic Ocean, but has spread around the world. It tunnels into underwater piers and pilings and is a major cause of damage and destruction to submarine timber structures and the hulls of wooden boats. Description ''Teredo navalis'' has an elongated, reddish, wormlike body which is completely enclosed in a tunnel it has made in floating or submerged timber. At the front end of the animal are two triangular, calcareous plates. These are up to long and correspond to the valves of other bivalve molluscs. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against France. The modern Royal Navy traces its origins to the early 16th century; the oldest of the UK's armed services, it is consequently known as the Senior Service. From the middle decades of the 17th century, and through the 18th century, the Royal Navy vied with the Dutch Navy and later with the French Navy for maritime supremacy. From the mid 18th century, it was the world's most powerful navy until the Second World War. The Royal Navy played a key part in establishing and defending the British Empire, and four Imperial fortress colonies and a string of imperial bases and coaling stations secured the Royal Navy's ability to assert naval superiority globally. Owing to this historical prominence, it is common, even among non-Britons, to ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winsor & Newton
Winsor & Newton (also abbreviated W&N) is an English manufacturing company based in London that produces a wide variety of fine art products, including acrylics, oils, watercolour, gouache, brushes, canvases, papers, inks, graphite and coloured pencils, markers, and charcoals. History The company was founded in 1832 by William Winsor and Henry Newton. The firm was originally located at Henry Newton's home in 38 Rathbone Place, London. This was then part of an artists' quarter in which a number of eminent painters, including Constable, had studios, and other colourmen were already established. The standards of quality for W&N's most renowned line of kolinsky sable brush, the Series 7, began after Queen Victoria ordered it should be "the very finest watercolour brush" in 1866. A few months before his death, Henry Newton sold the business to the newly incorporated firm of "Winsor & Newton Ltd.", which included members of both families amongst the shareholders. In 1937, W&N in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium Dioxide
Titanium dioxide, also known as titanium(IV) oxide or titania , is the inorganic compound with the chemical formula . When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. It is a white solid that is insoluble to water, although mineral forms can appear black. As a pigment, it has a wide range of applications, including paint, sunscreen, and food coloring. When used as a food coloring, it has E number E171. World production in 2014 exceeded 9 million tonnes. It has been estimated that titanium dioxide is used in two-thirds of all pigments, and pigments based on the oxide have been valued at a price of $13.2 billion. Structure In all three of its main dioxides, titanium exhibits octahedral geometry, being bonded to six oxide anions. The oxides in turn are bonded to three Ti centers. The overall crystal structure of rutile is tetragonal in symmetry whereas anatase and brookite are orthorhombic. The oxygen substructures are all slight distort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead Sulfide
Lead sulfide refers to two compounds containing lead and sulfur: *Lead(II) sulfide Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, le ..., PbS, containing lead in the +2 oxidation state, naturally occurring as the mineral galena * Lead(IV) sulfide, PbS2, containing lead in the +4 oxidation state {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The underground mine gas term for foul-smelling hydrogen sulfide-rich gas mixtures is ''stinkdamp''. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777. The British English spelling of this compound is hydrogen sulphide, a spelling no longer recommended by the Royal Society of Chemistry or the International Union of Pure and Applied Chemistry. Hydrogen sulfide is toxic to humans and most other animals by inhibiting cellular respiration in a manner similar to hydrogen cyanide. When it is inhaled or it or its salts are ingested in high amounts, damage to organs occurs rapidly with symptoms ranging from breathing difficulties to convulsions and death. Despite this, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
