Anisotropic crystal is a crystal that exhibits different properties when tested along axes in different directions.
Anisotropy is the property of molecules and materials to exhibit variations in physical properties along different molecular axes of the substance.
Avogadro’s law: Equal volumes of all gases contain equal numbers of molecules at the same pressure and temperature. The law, often called Avogadro’s hypothesis, is true only for ideal gases. It was proposed in 1811 by Italian chemist Amadeo Avogadro (1776-1856).
Bravais lattice is a set of points constructed by translating a single point in discrete steps by a set of basis vectors. The French crystallographer Auguste Bravais (1811-1863) established that in three-dimensional space only fourteen different lattices may be constructed. All crystalline materials recognised till now fit in one of these arrangements. The fourteen three-dimensional lattices, classified by crystal system, are shown to the bottom.
Crystal system
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Bravais lattices
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cubic a=b=c α=β=γ=90° |
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simple cubic
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body-centered cubic
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face-centered cubic
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tetragonal a=b≠c α=β=γ=90° |
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simple tetragonal
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body-centered tetragonal
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orthorhombic a≠b≠c α=β=γ=90° |
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simple orthorhombic
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base-centered orthorhombic
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body-centered orthorhombic
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face-centered orthorhombic
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monoclinic a≠b≠c α=γ=90°≠β |
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simple monoclinic
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base-centered monoclinic
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hexagonal a=b≠c α=β=90° γ=120° |
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hexagonal
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rhombohedral a=b=c α=β=γ≠90° |
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rhombohedral
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triclinic a≠b≠c α≠β≠γ≠90° |
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triclinic
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Some substance is a compound only if it can be decomposed into two or more different substances by means of a chemical reaction. If two or more substances react, thus creating a new substance, that new substance is called a chemical compound.
Brasses are alloys of copper and zinc (generally 5 % to 40 %). Brass has been known to man since prehistoric times, long before zinc itself was discovered. It was produced by melting copper together with calamine, a zinc ore. Its ductility reaches a maximum with about 30 % zinc and its tensile strength with 45 % although this property varies greatly with the mechanical and heat treatment of the alloy. Typical applications included gears, plumbing ware fittings, adapters, valves and screw machine products. The French horn is a valved brass wind instrument.
Brass may contain small amounts of other alloying elements, such as aluminum, lead, tin, or nickel. Lead can be added as an alloying element resulting in a brass that can be rapidly machined and produces minimal tool wear. Additions of aluminium, iron and manganese to brass improve strength, whilst silicon additions improve wear resistance. Brass containing tin (< 2 % ) is less liable to corrosion in seawater; it is sometimes called naval brass and is used in naval construction.
Contaminants are any physical, chemical, biological, or radiological substance or matter in water that may be harmful to human health or which degrade the palatability of water.
Robert Wilhem Bunsen (1811-1899) is a German chemist who held professorships at Kassel, Marburg and Heidelberg. His early researches on organometallic compound of arsenic cost him an eye in an explosion. Bunsen's most important work was in developing several techniques used in separating, identifying, and measuring various chemical substances. He also improvement chemical battery for use in isolating quantities of pure metals - Bunsen battery.
The essential piece of laboratory equipment that has immortalized the name of Bunsen was not invented by him. Bunsen improved the burner's design, which had been invented by Faraday, to aid his endeavors in spectroscopy. Use of the Bunsen burner in conjunction with a glass prism led to the development of the spectroscope in collaboration with the German physicist Gustav Kirchoff and to the spectroscopic discovery of the elements rubidium (1860) and cesium (1861).
Generalic, Eni. "Vaga s različitim krakovima." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
Glossary
Periodic Table