element

el·e·ment

E0084200 (ĕl′ə-mənt)n.1. A fundamental, essential, or irreducible constituent of a composite entity.2. elements The basic assumptions or principles of a subject.3. Mathematics a. A member of a set.b. A point, line, or plane.c. A part of a geometric configuration, such as an angle in a triangle.d. The generatrix of a geometric figure.e. Any of the terms in the rectangular array of terms that constitute a matrix or determinant.4. Chemistry & Physics A substance composed of atoms having an identical number of protons in each nucleus. Elements cannot be reduced to simpler substances by normal chemical means. See Periodic Table (pages 131X-131X).5. One of four substances, earth, air, fire, or water, formerly regarded as a fundamental constituent of the universe.6. Electricity The resistance wire in an electrical appliance such as a heater or an oven.7. elements The forces that constitute the weather, especially severe or inclement weather: outside paint that had been damaged by the elements.8. An environment naturally suited to or associated with an individual: He is in his element when traveling. The business world is her element.9. A distinct group within a larger community: the dissident element on campus.10. A part of a military force, especially:a. A ground unit in an air force comparable to a platoon.b. A unit of an air force equal to two or three aircraft.11. elements The bread and wine of the Eucharist.

[Middle English, from Old French, from Latin elementum, perhaps ultimately from lmn, first three letters of the second half of the Canaanite alphabet, recited by ancient scribes when learning it.]Synonyms: element, component, constituent, factor, ingredient
These nouns denote one of the individual parts of which a composite entity is made up: the grammatical elements of a sentence; real estate as a component of wealth; a protein that is a constituent of a virus; analyzed the factors that led to the accident; a cake made of flour, eggs, and other ingredients.

element

(ˈɛlɪmənt) n1. (Elements & Compounds) any of the 118 known substances (of which 93 occur naturally) that consist of atoms with the same number of protons in their nuclei. Compare compound¹¹2. one of the fundamental or irreducible components making up a whole3. a cause that contributes to a result; factor4. any group that is part of a larger unit, such as a military formation5. a small amount; hint: an element of sarcasm in her voice. 6. a distinguishable section of a social group: he belonged to the stable element in the expedition. 7. (Biology) the most favourable environment for an animal or plant8. the situation in which a person is happiest or most effective (esp in the phrases in or out of one's element)9. (Electrical Engineering) the resistance wire and its former, which constitute the electrical heater in a cooker, heater, etc10. (Electronics) electronics another name for component²11. (Philosophy) one of the four substances thought in ancient and medieval cosmology to constitute the universe (earth, air, water, or fire)12. (Physical Geography) (plural) atmospheric conditions or forces, esp wind, rain, and cold: exposed to the elements. 13. (plural) the first principles of a subject14. (Mathematics) geometry a point, line, plane, or part of a geometric figure15. (Mathematics) maths a. any of the terms in a determinant or matrixb. one of the infinitesimally small quantities summed by an integral, often represented by the expression following the integral sign: in ∫^baf(x)dx, f(x)dx is an element of area. 16. (Mathematics) maths logic one of the objects or numbers that together constitute a set17. (Ecclesiastical Terms) Christianity the bread or wine consecrated in the Eucharist18. (Astronomy) astronomy any of the numerical quantities, such as the major axis or eccentricity, used in describing the orbit of a planet, satellite, etc19. (Broadcasting) one of the vertical or horizontal rods forming a television or VHF radio receiving aerial20. (General Physics) physics a component of a compound lens[C13: from Latin elementum a first principle, alphabet, element, of uncertain origin]

el•e•ment

art at electrum (ˈɛl ə mənt)

n. 1. a component or constituent of a whole or one of the parts into which a whole may be resolved by analysis. 2. one of a class of substances that cannot be separated into simpler substances by chemical means. 3. a natural habitat, sphere of activity, or environment: to be in one's element. 4. elements, a. atmospheric forces; weather. b. the rudimentary principles of an art or science. c. the bread and wine of the Eucharistic service. 5. any group of people singled out, often with disapproval, as having identifiable behavior patterns, common goals, ethnic similarities, etc.: the radical element. 6. one of the substances, usu. earth, air, fire, and water, formerly regarded as constituting the material universe. 7. a component of a mechanical device: a printing element on a typewriter. 8. Math. a. an infinitesimal part of a given quantity, similar in nature to it. b. an entity that satisfies all the conditions of belonging to a given set. 9. one of the points, lines, planes, or other geometrical forms of which a figure is composed. [1250–1300; < Latin elementum one of the four elements, letter of the alphabet, first principle, rudiment] syn: element, component, constituent, ingredient refer to units that are parts of whole or complete substances, systems, compounds, or mixtures. element denotes a fundamental, ultimate part: elements of matter; elements of a problem. component refers to one of a number of separate parts: Iron and carbon are components of steel. constituent refers to an active and necessary part: The constituents of a molecule of water are two atoms of hydrogen and one of oxygen. ingredient is most frequently used in nonscientific contexts to denote any part that is combined into a mixture: the ingredients of a cake; the ingredients of a successful marriage.

el·e·ment

(ĕl′ə-mənt)1. A substance that cannot be broken down into simpler substances by chemical means. An element is composed of atoms that have the same atomic number; that is, each atom has the same number of protons in its nucleus as all other atoms of that element. Today 112 elements are known, of which 92 are known to occur in nature, while the remaining 20 have only been made with particle accelerators.2. Mathematics A member of a set.Word History The symbols that scientists use for the chemical elements are usually abbreviations of the elements' names. Thus the symbol for hydrogen is H, and the symbol for oxygen is O, both from the first letter of the name. But if you look at the Periodic Table at Periodic Table, you'll notice that some symbols are entirely different from the corresponding element names. The symbol for iron is Fe, and the symbol for tin is Sn, for example. Why is this? It happens that some elements were already known to the ancient Greeks and Romans, such as familiar metals like iron, copper, silver, gold, tin, and lead. For these elements scientists use abbreviations of the Greek and Latin words for them. The Latin words for the six metals listed above are ferrum, cuprum, argentum, aurum, stannum, and plumbum. From these names come, quite straightforwardly, the chemical symbols Fe, Cu, Ag, Au, Sn, and Pb.

element

1. The elements represent general characteristics that are linked with certain zodiac signs. There are four elements: fire, air, earth and water.2. One of four elements, Earth, Air, Fire or Water, believed to be particularly significant to magic ritual, for hundreds of years linked to other things (such as the planets and the signs of the zodiac), using a system of correspondences.3. A substance which cannot be split into simpler substances using chemical methods

Thesaurus

Noun	1.	element - an abstract part of something; "jealousy was a component of his character"; "two constituents of a musical composition are melody and harmony"; "the grammatical elements of a sentence"; "a key factor in her success"; "humor: an effective ingredient of a speech"component, factor, ingredient, constituentbe all and end all, be-all and end-all - the essential factor; the all-important element; the supreme aim; "profit is the be-all and end-all of business"plot element - a component or element of the plot of a storypoint - a geometric element that has position but no extension; "a point is defined by its coordinates"division, section, part - one of the portions into which something is regarded as divided and which together constitute a whole; "the written part of the exam"; "the finance section of the company"; "the BBC's engineering division"
	2.	element - an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system; "spare components for cars"; "a component or constituent element of a system"constituent, componentaccessory, add-on, appurtenance, supplement - a supplementary component that improves capabilityaddition, add-on, improver - a component that is added to something to improve it; "the addition of a bathroom was a major improvement"; "the addition of cinnamon improved the flavor"audio - the sound elements of televisionauto part, car part - a component of an automobile; "his business is auto parts"crystal - a crystalline element used as a component in various electronic devicescomputer hardware, hardware - (computer science) the mechanical, magnetic, electronic, and electrical components making up a computer systemheating element - the component of a heater or range that transforms fuel or electricity into heatingredient - a component of a mixture or compoundinput - a component of production; something that goes into the production of outputlandside - component consisting of a side piece opposite the moldboardmaking - (usually plural) the components needed for making or doing something; "the recipe listed all the makings for a chocolate cake"module - a self-contained component (unit or item) that is used in combination with other componentspart, portion - something less than the whole of a human artifact; "the rear part of the house"; "glue the two parts together"pel, picture element, pixel - (computer science) the smallest discrete component of an image or picture on a CRT screen (usually a colored dot); "the greater the number of pixels per inch the greater the resolution"retrofit - a component or accessory added to something after it has been manufacturedspare, spare part - an extra component of a machine or other apparatusspark gap - a component of an ignition system; consists of two shaped electrodes and the space between them
	3.	element - any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matterchemical elementsubstance - the real physical matter of which a person or thing consists; "DNA is the substance of our genes"atom - (physics and chemistry) the smallest component of an element having the chemical properties of the elementallotrope - a structurally different form of an element; "graphite and diamond are allotropes of carbon"transuranic element - any element having an atomic number greater than 92 (which is the atomic number of uranium); all are radioactiveargonon, inert gas, noble gas - any of the chemically inert gaseous elements of the helium group in the periodic tablemetal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.nonmetal - a chemical element lacking typical metallic propertiestransactinide - any of the artificially produced elements with atomic numbers greater than 103Ac, actinium, atomic number 89 - a radioactive element of the actinide series; found in uranium oresAr, argon, atomic number 18 - a colorless and odorless inert gas; one of the six inert gases; comprises approximately 1% of the earth's atmosphereAs, atomic number 33, arsenic - a very poisonous metallic element that has three allotropic forms; arsenic and arsenic compounds are used as herbicides and insecticides and various alloys; found in arsenopyrite and orpiment and realgarastatine, At, atomic number 85 - a highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thoriumatomic number 107, Bh, bohrium, element 107 - a transuranic elementatomic number 5, boron, B - a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powderatomic number 35, Br, bromine - a nonmetallic heavy volatile corrosive dark brown liquid element belonging to the halogens; found in sea wateratomic number 6, carbon, C - an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compoundsatomic number 17, chlorine, Cl - a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)atomic number 110, darmstadtium, Ds, element 110 - a radioactive transuranic elementatomic number 105, Db, dubnium, element 105, hahnium - a transuranic elementatomic number 9, fluorine, F - a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatiteatomic number 32, Ge, germanium - a brittle grey crystalline element that is a semiconducting metalloid (resembling silicon) used in transistors; occurs in germanite and argyroditeatomic number 108, element 108, hassium, Hs - a radioactive transuranic elementatomic number 2, He, helium - a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)atomic number 1, H, hydrogen - a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universeatomic number 53, I, iodin, iodine - a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks)atomic number 36, Kr, krypton - a colorless element that is one of the six inert gasses; occurs in trace amounts in airatomic number 103, lawrencium, Lr - a radioactive transuranic element synthesized from californiumatomic number 109, element 109, meitnerium, Mt - a radioactive transuranic elementatomic number 101, Md, mendelevium, Mv - a radioactive transuranic element synthesized by bombarding einsteinium with alpha particles (Md is the current symbol for mendelevium but Mv was formerly the symbol)atomic number 10, Ne, neon - a colorless odorless gaseous element that give a red glow in a vacuum tube; one of the six inert gasses; occurs in the air in small amountsatomic number 7, N, nitrogen - a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
	4.	element - the most favorable environment for a plant or animal; "water is the element of fishes"environs, surround, surroundings, environment - the area in which something exists or lives; "the country--the flat agricultural surround"
	5.	element - one of four substances thought in ancient and medieval cosmology to constitute the physical universe; "the alchemists believed that there were four elements"substance - the real physical matter of which a person or thing consists; "DNA is the substance of our genes"air - once thought to be one of four elements composing the universe (Empedocles)fire - once thought to be one of four elements composing the universe (Empedocles)earth - once thought to be one of four elements composing the universe (Empedocles)ether, quintessence - the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodieswater - once thought to be one of four elements composing the universe (Empedocles)
	6.	element - the situation in which you are happiest and most effective; "in your element"situation, state of affairs - the general state of things; the combination of circumstances at a given time; "the present international situation is dangerous"; "wondered how such a state of affairs had come about"; "eternal truths will be neither true nor eternal unless they have fresh meaning for every new social situation"- Franklin D.Roosevelt
	7.	element - a straight line that generates a cylinder or conestraight line - a line traced by a point traveling in a constant direction; a line of zero curvature; "the shortest distance between two points is a straight line"element of a cone - a straight line joining the apex and a point on the baseelement of a cylinder - a straight line running the length of the cylinder

element

noun1. component, part, feature, unit, section, factor, principle, aspect, foundation, ingredient, constituent, subdivision one of the key elements of the UN's peace plan2. group, faction, clique, set, party, circle The government must weed out criminal elements from the security forces.3. trace, suggestion, hint, dash, suspicion, tinge, smattering, soupçon There is an element of truth in his accusation.plural noun1. weather conditions, climate, the weather, wind and rain, atmospheric conditions, powers of nature, atmospheric forces The area is exposed to the elements.be in your element be in a situation you enjoy, be in your natural environment, be in familiar surroundings My stepmother was in her element, organizing everyone.

element

noun1. A fundamental irreducible constituent of a whole:basic, essential, fundamental, rudiment (often used in plural).Idiom: part and parcel.2. One of the individual entities contributing to a whole:building block, component, constituent, factor, ingredient, integrant, part.3. An individually considered portion of a whole:article, detail, item, particular, point.

Translations

要素元素小量电热元件电阻丝

element

(ˈeləmənt) noun1. an essential part of anything. Sound teaching of grammar is one of the elements of a good education.要素2. a substance that cannot be split by chemical means into simpler substances. Hydrogen, chlorine, iron and uranium are elements.元素3. surroundings necessary for life. Water is a fish's natural element.自然的生存环境4. a slight amount. an element of doubt.小量5. the heating part in an electric kettle etc. 电热元件，电阻丝 ˌeleˈmentary (-ˈmen-) adjective very simple; not advanced. elementary mathematics.初级的ˈelements noun plural1. the first things to be learned in any subject. the elements of musical theory. 原理，基础 2. the forces of nature, as wind and rain. 自然力（用复数表示，如风、雨） in one's element in the surroundings that are most natural or pleasing to one. 处于适宜的环境

element

→ 要素zhCN

element

See also: Elements (table)Elements
Element Symbol Atomic Number Atomic Weight¹ Melting Point
(Degrees Celsius)
Boiling Point
(Degrees Celsius)

actinium Ac 89 (227) 1050. 3200. ±300
aluminum Al 13 26.98154 660.37 2467.
americium Am 95 (243) 1172. 2600.
..... Click the link for more information.

element,

in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compoundcompound,
in chemistry, a substance composed of atoms of two or more elements in chemical combination, occurring in a fixed, definite proportion and arranged in a fixed, definite structure. A compound is often represented by its chemical formula.
..... Click the link for more information. can be decomposed into its constituent elements by means of a chemical reaction, but no further simplification can be achieved. An element can, however, be decomposed into simpler substances, such as protons and neutrons or various combinations of them, by the methods of particle physics, e.g., by bombardment of the nucleus.

The Atom

The smallest unit of a chemical element that has the properties of that element is called an atomatom
[Gr.,=uncuttable (indivisible)], basic unit of matter; more properly, the smallest unit of a chemical element having the properties of that element. Structure of the Atom
..... Click the link for more information. . Many elements (e.g., helium) occur as single atoms. Other elements occur as molecules made up of more than one atom. Elements that ordinarily occur as diatomic molecules include hydrogen, nitrogen, oxygen, and the halogens, but oxygen also occurs as a triatomic form called ozone. Phosphorus usually occurs as a tetratomic molecule, and crystalline sulfur occurs as molecules containing eight atoms.

Atomic Number and Mass Number

Regardless of how many atoms the element is composed of, each atom has the same number of protons in its nucleus, and this is different from the number in the nucleus of any other element. Thus this number, called the atomic number (at. no.), defines the element. For example, the element carbon consists of atoms all with at. no. 6, i.e., all having 6 protons in the nucleus; any atom with at. no. 6 is a carbon atom. By 2016, 118 elements were known, ranging from hydrogen with an at. no. of 1 to oganesson with an at. no. of 118. (See the table entitled ElementsElements
Element Symbol Atomic Number Atomic Weight¹ Melting Point
(Degrees Celsius)
Boiling Point
(Degrees Celsius)

actinium Ac 89 (227) 1050. 3200. ±300
aluminum Al 13 26.98154 660.37 2467.
americium Am 95 (243) 1172. 2600.
..... Click the link for more information. for an alphabetical list of all the elements, including their symbols, atomic numbers, atomic weights, and melting and boiling points.) The nuclei of most atoms also contain neutrons. The total number of protons and neutrons in the nucleus of an atom is called the mass number. For example, the mass number of a carbon atom with 6 protons and 6 neutrons in its nucleus is 12.

Isotopes

Although all atoms of an element have the same number of protons in their nuclei, they may not all have the same number of neutrons. Atoms of an element with the same mass number make up an isotopeisotope
, in chemistry and physics, one of two or more atoms having the same atomic number but differing in atomic weight and mass number. The concept of isotope was introduced by F.
..... Click the link for more information. of the element. All known elements have isotopes; some have more than others. Hydrogen, for example, has only 3 isotopes, while xenon has 16. Approximately 300 naturally occurring isotopes are known, and more than 2,500 radioactive isotopes have been artificially produced (see synthetic elementssynthetic elements,
in chemistry, radioactive elements that were not discovered occurring in nature but as artificially produced isotopes. They are technetium (at. no. 43), which was the first element to be synthesized, promethium (at. no. 61), astatine (at. no.
..... Click the link for more information. ). There are 13 isotopes of carbon, having from 2 to 14 neutrons in the nucleus and therefore mass numbers from 8 to 20.

Not all of the elements have stable isotopes. Some have only radioactive isotopes, which decay to form other isotopes, usually of other elements (see radioactivityradioactivity,
spontaneous disintegration or decay of the nucleus of an atom by emission of particles, usually accompanied by electromagnetic radiation. The energy produced by radioactivity has important military and industrial applications.
..... Click the link for more information. ). In some cases all the isotopes of an element are very unstable, and the element is therefore not found in nature. Only 94 of the elements are known to occur naturally on earth. Of these, 6 occur in minute amounts produced by the decay of other elements. These 6 extremely scarce elements and those that do not occur at all naturally were discovered when they were produced in the laboratory; they are often called the artificially produced or synthetic elementssynthetic elements,
in chemistry, radioactive elements that were not discovered occurring in nature but as artificially produced isotopes. They are technetium (at. no. 43), which was the first element to be synthesized, promethium (at. no. 61), astatine (at. no.
..... Click the link for more information. .

Atomic Mass and Atomic Weight

Atoms are not very massive; a carbon atom weighs about 2 × 10⁻²³ grams. Because atoms have so little mass, a unit much smaller than the gram is used. In the current system (adopted in 1960–61) the unit of atomic mass, called atomic mass unitatomic mass unit
or amu,
in chemistry and physics, unit defined as exactly 1-12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is equal to approximately 1.66 × 10⁻²⁴ grams.
..... Click the link for more information. (amu), is defined as exactly 1-12 the mass of an atom of carbon-12. The atomic weightatomic weight,
mean (weighted average) of the masses of all the naturally occurring isotopes of a chemical element, as contrasted with atomic mass, which is the mass of any individual isotope. Although the first atomic weights were calculated at the beginning of the 19th cent.
..... Click the link for more information. of an element is the mean (weighted average) of the atomic masses of all the naturally occurring isotopes. Carbon has two principal naturally occurring isotopes, carbon-12 and carbon-13. Carbon-12, whose mass is defined as exactly 12 amu, constitutes 98.89% of naturally occurring carbon; carbon-13, whose mass is 13.00335 amu, constitutes 1.11%. (There are also small traces of the radioactive isotope carbon-14.) The atomic weight of the element is determined by multiplying the percent abundance of each isotope by the atomic mass of the isotope, adding these products, and dividing by 100. However, isotope abundance is often determined by the medium of the source, solid, liquid, or gas, and the average atomic weight may fluctuate. Thus, for carbon, [(98.89 × 12.000) + (1.11 × 13.00335)]/100 = 12.01115, which is the atomic weight of the element carbon in amu, but because the proportions of the isotopes vary depending on where the carbon is found, carbon's atomic weight is now expressed as an interval defined by the lower and upper bounds within which the atomic weight ranges: [12.0096; 12.0116]. Certain synthetic elements exist only momentarily in the form of a few short-lived isotopes; in such cases the concept of atomic weight cannot be applied.

Properties of the Elements

Properties of an element are sometimes classed as either chemical or physical. Chemical properties are usually observed in the course of a chemical reaction, while physical properties are observed by examining a sample of the pure element. The chemical properties of an element are due to the distribution of electrons around the atom's nucleus, particularly the outer, or valence, electrons; it is these electrons that are involved in chemical reactions. A chemical reaction does not affect the atomic nucleus; the atomic number therefore remains unchanged in a chemical reaction.

Some properties of an element can be observed only in a collection of atoms or molecules of the element. These properties include color, density, melting point, boiling point, and thermal and electrical conductivity. While some of these properties are due chiefly to the electronic structure of the element, others are more closely related to properties of the nucleus, e.g., mass number.

The elements are sometimes grouped according to their properties. One major classification of the elements is as metalsmetal,
chemical element displaying certain properties by which it is normally distinguished from a nonmetal, notably its metallic luster, the capacity to lose electrons and form a positive ion, and the ability to conduct heat and electricity.
..... Click the link for more information. , nonmetalsnonmetal,
chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and form negative ions and that its oxide is acidic.
..... Click the link for more information. , and metalloids. Elements with very similar chemical properties are often referred to as families; some families of elements include the halogens, the inert gases, and the alkali metals. In the periodic tableperiodic table,
chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled
..... Click the link for more information. the elements are arranged in order of increasing atomic weight in such a way that the elements in any column have similar properties.

Official Symbols and Names for the Elements

Each element is assigned an official symbol by the International Union of Pure and Applied Chemistry (IUPAC). For example, the symbol for carbon is C, and the symbol for silver is Ag [Lat. argentum = silver]. There are several ways of designating an isotope. One designation consists of the name or symbol of the element followed by a hyphen and the mass number of the isotope; thus the isotope of carbon with mass number 12 can be designated carbon-12 or C-12. The mass number is often written as a superscript, e.g., C¹²; sometimes the atomic number is written as a subscript preceding the symbol, e.g., ₆C¹². The IUPAC rules for nomenclature of inorganic chemistry state that the subscript atomic number and superscript mass number should both precede the symbol, e.g., ¹²₆C.

Many isotopes were given special names and symbols when they were first discovered in natural radioactive decay series (e.g., uranium-235 was called actinouranium and represented by the symbol AcU). This practice is discouraged in the modern nomenclature except in the case of hydrogen. The isotopes hydrogen-2 and hydrogen-3 are usually called deuterium and tritium, respectively. Hydrogen-1, the most abundant isotope, has the name protium but is usually simply called hydrogen. Newly discovered elements that have been synthesized by one laboratory and not yet confirmed by a second are given a provisional name based on Greek and Latin roots; when the discovery is confirmed, the laboratory that first made it may suggest a name for the element.

The Elements through the Ages

Some elements have been known since antiquity. Gold ornaments from the Neolithic period have been discovered. Gold, iron, copper, lead, silver, and tin were used in Egypt and Mesopotamia before 3000 B.C. However, recognition of these metals as chemical elements did not occur until modern times.

Greek Concept of the Elements

The Greek philosophers proposed that there are basic substances from which all things are made. EmpedoclesEmpedocles
, c.495–c.435 B.C., Greek philosopher, b. Acragas (present Agrigento), Sicily. Leader of the democratic faction in his native city, he was offered the crown, which he refused. A turn in political fortunes drove him and his followers into exile.
..... Click the link for more information. proposed four basic "roots," earth, air, fire, and water, and two forces, harmony and discord, joining and separating them. PlatoPlato
, 427?–347 B.C., Greek philosopher. Plato's teachings have been among the most influential in the history of Western civilization. Life

After pursuing the liberal studies of his day, he became in 407 B.C. a pupil and friend of Socrates. From about 388 B.
..... Click the link for more information. called the roots stoicheia (elements). He thought that they assume geometric forms and are made up of some more basic but undefined matter. A different theory, that of LeucippusLeucippus
, 5th cent. B.C., Greek philosopher. Aristotle believed that Leucippus inspired the atomistic theory with which Democritus is identified. Little is known about Leucippus.
..... Click the link for more information. and his followers, held that all matter is made up of tiny indivisible particles (atomos).

This theory was rejected by AristotleAristotle
, 384–322 B.C., Greek philosopher, b. Stagira. He is sometimes called the Stagirite. Life

Aristotle's father, Nicomachus, was a noted physician. Aristotle studied (367–347 B.C.
..... Click the link for more information. , who expanded on Plato's theory. Aristotle believed that different forms (eidos) were assumed by a basic material, which he called hulé. The hulé had four basic properties, hotness, coldness, dryness, and moistness. The four elements differ in their embodiment of these properties; fire is hot and dry, earth cold and dry, water cold and moist, and air hot and moist. Although Aristotle proposed that an element is "one of those simple bodies into which other bodies can be decomposed and which itself is not capable of being divided into others," he thought the metals to be made of water, and called mercury "silver water" (chutos arguros). His idea that matter was a single basic substance that assumed different forms led to attempts by the alchemists to transmute other metals into gold.

Evolution of Modern Concepts

Although much early work was done in chemistry, especially with metals, and many recipes were recorded, there were few developments in the conception of the elements. In the 16th cent. ParacelsusParacelsus, Philippus Aureolus
, 1493?–1541, Swiss physician and alchemist. His original name Theophrastus Bombastus von Hohenheim. He traveled widely, acquiring knowledge of alchemy, chemistry, and metallurgy, and although his egotism and his contempt for traditional
..... Click the link for more information. proposed salt, mercury, and sulfur as three "principles" of which bodies were made, although he apparently also believed in the four "elements." Van Helmont (c.1600) rejected the four elements and three principles, substituting two elements, air and water.

Robert BoyleBoyle, Robert,
1627–91, Anglo-Irish physicist and chemist. The seventh son of the 1st earl of Cork, he was educated at Eton and on the Continent and conducted most of his researches at his own laboratories at Oxford (1654–68) and London (1668–91).
..... Click the link for more information. rejected these early theories and proposed a definition of chemical elements that led to the currently accepted definition. His definition is strikingly similar to Aristotle's earlier definition. In The Sceptical Chymist (1661) Boyle wrote, "I now mean by elements … certain primitive and simple, or perfectly unmingled bodies; which not being made of any other bodies, or of one another, are the ingredients of which all those called perfectly mixed bodies [chemical compounds] are immediately compounded, and into which they are ultimately resolved."

Whereas Aristotle and other early philosophers tried to determine the identity of the elements solely by reason, Boyle and later scientists used the results of numerous experiments to identify the elements. In 1789 Antoine LavoisierLavoisier, Antoine Laurent
, 1743–94, French chemist and physicist, a founder of modern chemistry. He studied under eminent men of his day, won early recognition, and was admitted to the Academy of Sciences in 1768.
..... Click the link for more information. published a list of chemical elements based on Boyle's definition; this encouraged adoption of standard names for the elements. Although some of his elements are now known to be compounds, such as metallic oxides and salts, they were at the time accepted as elements since they could not be decomposed by any method then known.

In 1803 John DaltonDalton, John
, 1766–1844, English scientist. He revived the atomic theory (see atom), which he formulated in the first volume of his New System of Chemical Philosophy (2 vol., 1808–27).
..... Click the link for more information. proposed (as part of his atomic theory) that all atoms of an element have identical properties (including mass), that these atoms are unchanged by chemical action, and that atoms of different elements react with one another in simple proportions. Although symbols for some of the elements already existed, they were by no means universally accepted, and each compound also had a unique symbol that was unrelated to its chemical composition. Dalton devised a new set of circular symbols for the elements and used a combination of elemental symbols to represent a compound. For example, his symbol for oxygen was ◯, and for hydrogen ⊙. Since he thought water contained one atom of hydrogen for every atom of oxygen, he formed the symbol for water by writing the symbols for hydrogen and oxygen touching one another, ⊙◯. J. J. BerzeliusBerzelius, Jöns Jakob, Baron
, 1779–1848, Swedish chemist, M.D. Univ. of Uppsala, 1802. He was noted for his work as teacher at the medical school and other institutions in Stockholm and for his discoveries in diverse fields of chemistry.
..... Click the link for more information. was the first to use the modern method, letting one or two letters of the element's name serve as its symbol. He also published an early table of atomic weights of 24 elements with most values very close to those now in use.

Discovery of the Elements

As noted above, some of the elements were discovered in prehistoric times but were not recognized as elements. Arsenic was discovered around 1250 by Albertus MagnusAlbertus Magnus, Saint
, or Saint Albert the Great,
b. 1193 or 1206, d. 1280, scholastic philosopher, Doctor of the Church, called the Universal Doctor. A nobleman of Bollstädt in Swabia, he joined (1223) the Dominicans and taught at Hildesheim, Freiburg,
..... Click the link for more information. , and phosphorus was discovered about 1674 by Hennig Brand, an alchemist, who prepared it by distilling human urine. Only 12 elements were known before 1700, and only about twice that many by 1800, but by 1900 over 80 elements had been identified. In 1919 Ernest RutherfordRutherford, Ernest Rutherford, 1st Baron,
1871–1937, British physicist, b. New Zealand. Rutherford left New Zealand in 1895, having earned three degrees from the Univ.
..... Click the link for more information. found that hydrogen was given off when nitrogen was bombarded with alpha particles. This first transmutation encouraged further study of nuclear reactions, and eventually led to the discovery in 1937 of technetium, the first synthetic element. Neptunium (atomic number 93) was the first transuranium elementtransuranium elements,
in chemistry, radioactive elements with atomic numbers greater than that of uranium (at. no. 92). All the transuranium elements of the actinide series were discovered as synthetic radioactive isotopes at the Univ.
..... Click the link for more information. to be synthesized (1940). Its discovery prompted the search that has led to the ongoing synthesis of additional transuranium elements.

Bibliography

See J. Emsley, The Elements (1991); A. Swertka, A Guide to the Elements (1996); P. W. Atkins, The Periodic Kingdom (1997); N. N. Greenwood and A. Earnshaw, Chemistry of the Elements (2d ed. 1997).

element

(el -ĕ-mĕnt) Any of a large number of substances, including hydrogen, helium, carbon, nitrogen, oxygen, and iron, that consist entirely of atoms of the same atomic number, i.e. with the same number of protons in their nuclei. The atoms are not all identical however: isotopes of an element can occur with different numbers of neutrons in their nuclei. When arranged in order of increasing atomic number along a series of horizontal rows, elements with similar chemical and physical properties fall into groups. The similarities in properties arise from similarities in the electron arrangements within the atom. This table of elements is called the periodic table. Over 100 elements are now known, more than 90 of which occur naturally on Earth. The elements have stable isotopes and/or unstable (i.e. radioactive) isotopes.

The creation of the elements and the means by which they become distributed throughout the Universe are major areas of study in astronomy (see nucleosynthesis). The abundance of each element in the Universe, i.e. its cosmic abundance, depends on the method of its synthesis – by nuclear reactions in stars, by cosmic-ray collisions, etc. – and on its lifetime in its immediate surroundings and its long-term stability.

Element

An integral part of the sub- or superstructure having its own functional requirements; such as foundations, walls, floors, roofs, stairs and structural framework.

Element

(1) Among ancient Greek materialist philosophers, the basic constituents of nature; Empedocles believed the four basic elements to be fire, air, water, and earth. In ancient Chinese philosophy, the basic elements were thought to be metal, earth, water, wood, and fire.

(2) In the plural, a phenomenon or force of nature, such as a storm, that is regarded as irrepressible.

(3) In a figurative sense, one’s habitual environment or surroundings; a favorite, familiar occupation or pursuit.

element

[′el·ə·mənt] (chemistry) A substance made up of atoms with the same atomic number; common examples are hydrogen, gold, and iron. Also known as chemical element. (computer science) A circuit or device performing some specific elementary data-processing function. (electricity) A part of an electron tube, semiconductor device, or antenna array that contributes directly to the electrical performance. (mathematics) component (electromagnetism) Radiator, active or parasitic, that is a part of an antenna. (industrial engineering) A brief, relatively homogeneous part of a work cycle that can be described and identified. (mathematics) In an array such as a matrix or determinant, a quantity identified by the intersection of a given row or column. In network topology, an edge. The generatrix of a ruled surface at any one fixed position. (civil engineering) member

building element

An architectural component of a building, facility, or site.

element

1. any of the 118 known substances (of which 93 occur naturally) that consist of atoms with the same number of protons in their nuclei 2. the most favourable environment for an animal or plant 3. the resistance wire and its former that constitute the electrical heater in a cooker, heater, etc. 4. Electronics another name for component5. one of the four substances thought in ancient and medieval cosmology to constitute the universe (earth, air, water, or fire) 6. atmospheric conditions or forces, esp wind, rain, and cold 7. Geometry a point, line, plane, or part of a geometric figure 8. Mathsa. any of the terms in a determinant or matrix b. one of the infinitesimally small quantities summed by an integral, often represented by the expression following the integral sign 9. Maths Logic one of the objects or numbers that together constitute a set 10. Christianity the bread or wine consecrated in the Eucharist 11. Astronomy any of the numerical quantities, such as the major axis or eccentricity, used in describing the orbit of a planet, satellite, etc. 12. Physics a component of a compound lens

element

(data, programming)One of the items of data in an array.

element

(language, text)One kind of node in an SGML, HTML, orXML document tree. An SGML element is typicallyrepresented by a start tag ("

") and an end tag ("

").In some SGML implementations, some tags are omissible, as with"" in HTML.

The start tag can contain attributes ("

"), which are an unordered set of key-valuebindings for that element. Both the start tag and end tag foran element typically contain the "tag name" (also called the"GI" or generic identifier) for that element.

In XML, an element is always represented either by anexplicit start tag and end tag, or by an empty element tag(" a dodad ").

Other kinds of SGML node are: a section of character data("foo"), a comment (""), a markup declaration("").

element

el·e·ment

element

el•e•ment

el·e·ment

element

element

element

element

element

element

brave the elements

element of surprise

be in (one's) element

be out of (one's) element

in (one's) element

out of (one's) element

in one's element

*out of one's element

brave the elements

in one's element

out of one's element

in your element

in (or out of) your element

in your ˈelement

out of your ˈelement

brave the elements, to

in one's element

element

element,

The Atom

Atomic Number and Mass Number

Isotopes

Atomic Mass and Atomic Weight

Properties of the Elements

Official Symbols and Names for the Elements

The Elements through the Ages

Greek Concept of the Elements

Evolution of Modern Concepts

Discovery of the Elements

Bibliography

element

Element

Element

element

building element

element

element

element

element

element

el·e·ment

element

el·e·ment

element

mobile element

movable genetic element

rare earth element

trace element

ultratrace element

element

el·e·ment

Patient discussion about element

Element

Element

element

element

Synonyms for element

noun component

Synonyms

noun group

Synonyms

noun trace

Synonyms

noun weather conditions

Synonyms

phrase be in your element

Synonyms

Synonyms for element

noun a fundamental irreducible constituent of a whole