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Voltaic Pile
upright=1.2, Schematic diagram of a copper–zinc voltaic pile. Each copper–zinc pair had a spacer in the middle, made of cardboard or felt soaked in salt water (the electrolyte). Volta's original piles contained an additional zinc disk at the bottom, and an additional copper disk at the top; these were later shown to be unnecessary. file:VoltaBattery.JPG, upA voltaic pile on display in the ''Tempio Voltiano'' (the Volta Temple) near Volta's home in Como, Italy The voltaic pile was the first electrical battery that could continuously provide an electric current to a circuit. It was invented by Italian chemist Alessandro Volta, who published his experiments in 1799. Its invention can be traced back to an argument between Volta and Luigi Galvani, Volta's fellow Italian scientist who had conducted experiments on frogs' legs. Use of the voltaic pile enabled a rapid series of other discoveries, including the electrical decomposition (electrolysis) of water into oxygen and hydrogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daniell Cell
The Daniell cell is a type of electrochemical cell invented in 1836 by John Frederic Daniell, a British chemist and meteorologist, and consists of a copper pot filled with a copper (II) sulfate solution, in which is immersed an unglazed earthenware container filled with sulfuric acid and a zinc electrode. He was searching for a way to eliminate the hydrogen bubble problem found in the voltaic pile, and his solution was to use a second electrolyte to consume the hydrogen produced by the first. Zinc sulfate may be substituted for the sulfuric acid. The Daniell cell was a great improvement over the existing technology used in the early days of battery development. A later variant of the Daniell cell called the gravity cell or crowfoot cell was invented in the 1860s by a Frenchman named Callaud and became a popular choice for electrical telegraphy. The Daniell cell is also the historical basis for the contemporary definition of the volt, which is the unit of electromotive force in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Western Europe, with a population of 14.9 million. London stands on the River Thames in southeast England, at the head of a tidal estuary down to the North Sea, and has been a major settlement for nearly 2,000 years. Its ancient core and financial centre, the City of London, was founded by the Roman Empire, Romans as Londinium and has retained its medieval boundaries. The City of Westminster, to the west of the City of London, has been the centuries-long host of Government of the United Kingdom, the national government and Parliament of the United Kingdom, parliament. London grew rapidly 19th-century London, in the 19th century, becoming the world's List of largest cities throughout history, largest city at the time. Since the 19th cen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Gassner
Carl Gassner was a German physician (17 November 1855 in Mainz31 January 1942), scientist and inventor, better known to have contributed to improve the Leclanché cell and to have fostered the development of the first dry cell, also known as the zinc–carbon battery, less likely to break or leak and that could be effectively industrially produced at large scale. Life Gassner studied the medicine at the University of Strasbourg and then practiced in Mainz (Germany) as a specialist in diseases of the eyes and ears. He also conducted experiments in physics and chemistry at the Balbach watchmaking industry. Invention of dry cell In 1880, most of the door bells operated with a wet Leclanché cell containing an aqueous electrolyte solution which often dried out, rendering the cell unusable. To remediate this inconvenience, in 1876, Georges Leclanché started to jellify the electrolyte of his cell by adding starch to the ammonium chloride, making also his cell more portable. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volta Batteries
Volta may refer to: Persons * Alessandro Volta (1745–1827), Italian physicist and inventor of the electric battery, count and eponym of the volt * Giovanni Volta (1928–2012), Italian Roman Catholic bishop * Giovanni Serafino Volta (1764–1842) Italian priest, naturalist and paleontologist * Massimo Volta (born 1987), Italian footballer * Leopoldo Camillo Volta (1751–1823) Italian librarian and historian of Mantua Places * Volta, California, a census-designated place in Merced County, California, US * Volta Mantovana, an Italian municipality in the Lombardy region * Porta Volta, a former city gate of Milan, Italy * Volta Grande, a Brazilian municipality in the Minas Gerais state * Volta Redonda, a Brazilian municipality in the Rio de Janeiro state * Upper Volta (other) * Lake Volta, in Ghana * Volta Region, in Ghana * Volta River, primarily flowing in Ghana, with its headstreams: ** White Volta ** Red Volta ** Black Volta * Volta (crater), a crater on the Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University History Museum, University Of Pavia
The University History Museum of the University of Pavia () is a museum displaying memorabilia related to the history of the university, particularly in the fields of physics and medicine, when students were taught by prominent scholars such as Antonio Scarpa and Camillo Golgi or the physicist Alessandro Volta. The museum was founded in 1936 and is currently located at Palazzo Centrale. It currently forms the University of Pavia museum network, along with five other museums — the Natural History Museum, Museum of Electrical Technology, Museum of Archeology, Museum Camillo Golgi and Museum of Mineralogy. History The origin of the museum could be traced back to the end of the 18th century during the age of enlightenment era, when empress Maria Theresa of Austria ordered the reformation of the university teachings and structures. A Teaching Plan () and a Scientific Plan () were approved by the Magistrate of the General Studies in 1771 and 1773, respectively. These plans regulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Current (electricity)
An electric current is a flow of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is defined as the net rate of flow of electric charge through a surface. The moving particles are called charge carriers, which may be one of several types of particles, depending on the conductor. In electric circuits the charge carriers are often electrons moving through a wire. In semiconductors they can be electrons or holes. In an electrolyte the charge carriers are ions, while in plasma, an ionized gas, they are ions and electrons. In the International System of Units (SI), electric current is expressed in units of ampere (sometimes called an "amp", symbol A), which is equivalent to one coulomb per second. The ampere is an SI base unit and electric current is a base quantity in the International System of Quantities (ISQ). Electric current is also known as amperage and is measured using a device called an ''ammeter''. Electric currents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Chemical Education
The ''Journal of Chemical Education'' is a monthly peer-reviewed academic journal available in both print and electronic versions. It is published by the Division of Chemical Education of the American Chemical Society The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all ... and was established in 1924 by Neil Gordon. The journal covers research on chemical education, and its target audience includes instructors of chemistry from middle school through graduate school and some scientists in commerce, industry, and government. References External links * Chemical education journals American Chemical Society academic journals Monthly journals Academic journals established in 1924 English-language journals {{chemistry-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrode
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or a gas). In electrochemical cells, electrodes are essential parts that can consist of a variety of materials (chemicals) depending on the type of cell. An electrode may be called either a cathode or anode according to the direction of the electric current, unrelated to the potential difference between electrodes. Michael Faraday coined the term "" in 1833; the word recalls the Greek ἤλεκτρον (, "amber") and ὁδός (, "path, way"). The electrophore, invented by Johan Wilcke in 1762, was an early version of an electrode used to study static electricity. Anode and cathode in electrochemical cells Electrodes are an essential part of any battery. The first electrochemical battery was devised by Alessandro Volta and was aptly named the Voltaic cell. This battery consisted of a stack of copper and zinc electrodes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron, an import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. Silver is found in the Earth's crust in the pure, free elemental form ("native metal, native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc Refining (metallurgy), refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes bimetallism, alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Other than in currency and as an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable, unalloyed metallic form. This means that copper is a native metal. This led to very early human use in several regions, from . Thousands of years later, it was the first metal to be smelted from sulfide ores, ; the first metal to be cast into a shape in a mold, ; and the first metal to be purposely alloyed with another metal, tin, to create bronze, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
