metal

a hard substance such as gold, silver, or copper
Not to be confused with:mettle – inherent quality of character; fortitude; courage

met·al

M0244800 (mĕt′l)n.1. Any of a category of electropositive elements that usually have a shiny surface, are generally good conductors of heat and electricity, and can be melted or fused, hammered into thin sheets, or drawn into wires. Typical metals form salts with nonmetals, basic oxides with oxygen, and alloys with one another.2. An alloy of two or more metallic elements.3. An object made of metal.4. Basic character; mettle.5. Broken stones used for road surfaces or railroad beds.6. Molten glass, especially when used in glassmaking.7. Molten cast iron.8. Printing Type made of metal.9. Music Heavy metal.tr.v. met·aled, met·al·ing, met·als also met·alled or met·al·ling To cover or surface (a roadbed, for example) with broken stones.

[Middle English, from Old French, from Latin metallum, from Greek metallon, mine, ore, metal.]

metal

(ˈmɛtəl) n1. (Elements & Compounds) a. any of a number of chemical elements, such as iron or copper, that are often lustrous ductile solids, have basic oxides, form positive ions, and are good conductors of heat and electricityb. an alloy, such as brass or steel, containing one or more of these elements2. (Printing, Lithography & Bookbinding) printing type made of metal3. (Ceramics) the substance of glass in a molten state or as the finished product4. (Civil Engineering) short for road metal5. (Pop Music) informal short for heavy metal¹6. (Military) navy a. the total weight of projectiles that can be shot by a ship's guns at any one timeb. the total weight or number of a ship's guns7. (Elements & Compounds) astronomy Also called: heavy element any element heavier than helium8. (Heraldry) heraldry gold or silver9. (Railways) (plural) the rails of a railwayadjmade of metalvb (tr) , -als, -alling or -alled, -als, -aling or -aled10. (Metallurgy) to fit or cover with metal11. (Civil Engineering) to make or mend (a road) with road metal[C13: from Latin metallum mine, product of a mine, from Greek metallon] ˈmetal-ˌlike adj

met•al

(ˈmɛt l)

n., v. -aled, -al•ing (esp. Brit.) -alled, -al•ling. n. 1. any of a class of elementary substances, as gold, silver, or copper, all of which are crystalline when solid and many of which are characterized by opacity, ductility, conductivity, and a unique luster when freshly fractured. 2. such a substance in its pure state, as distinguished from alloys. 3. an alloy or mixture of such substances, as brass. 4. an element yielding positively charged ions in aqueous solutions of its salts. 5. formative material; stuff. 6. mettle. 7. printing type made of metallic alloy. 8. molten glass in the pot or melting tank. 9. road metal. 10. heavy metal. v.t. 11. to furnish or cover with metal. [1250–1300; Middle English (< Old French) < Latin metallum quarry, metal < Greek métallon] met′al•like`, adj.

metal.

1. metallurgical. 2. metallurgy.

met·al

(mĕt′l)1. Any of a large group of elements, including iron, gold, copper, lead, and magnesium, that conduct heat and electricity well. Metals can be hammered into thin sheets or drawn into wires. They are usually shiny and opaque. All metals except mercury are solid at room temperature.2. An alloy, such as steel or bronze, made of two or more metals.Usage We think of metals as hard, shiny materials used to make things like paper clips and cars. But for chemists, a metal is a chemical element that loses electrons in a chemical reaction. Metal atoms do this because of the structure of their electron shells—the layers in which electrons are arranged around an atom's nucleus. If an element's outermost electron shell is filled, the element is stable and does not react easily. But if the shell contains only a few electrons, the atom will try to share them with another atom in a chemical reaction, thereby becoming stable. Elements having only one electron in their outermost shell are the most reactive; all they have to do to become stable is lose this electron. Such elements are alkali metals like sodium and potassium, and they are listed in the left-hand column of the Periodic Table at Periodic Table. The metals farther toward the right side of the Periodic Table, such as tin and lead, have more electrons in their outermost shell and are not as reactive because sharing or losing all these electrons would require more energy. The elements that fall between these extremes are somewhat reactive and are called transition elements. They include elements like iron, copper, tungsten, and silver.

metal

Past participle: metalled
Gerund: metalling

Imperative
metal
metal

Present
I metal
you metal
he/she/it metals
we metal
you metal
they metal

Preterite
I metalled
you metalled
he/she/it metalled
we metalled
you metalled
they metalled

Present Continuous
I am metalling
you are metalling
he/she/it is metalling
we are metalling
you are metalling
they are metalling

Present Perfect
I have metalled
you have metalled
he/she/it has metalled
we have metalled
you have metalled
they have metalled

Past Continuous
I was metalling
you were metalling
he/she/it was metalling
we were metalling
you were metalling
they were metalling

Past Perfect
I had metalled
you had metalled
he/she/it had metalled
we had metalled
you had metalled
they had metalled

Future
I will metal
you will metal
he/she/it will metal
we will metal
you will metal
they will metal

Future Perfect
I will have metalled
you will have metalled
he/she/it will have metalled
we will have metalled
you will have metalled
they will have metalled

Future Continuous
I will be metalling
you will be metalling
he/she/it will be metalling
we will be metalling
you will be metalling
they will be metalling

Present Perfect Continuous
I have been metalling
you have been metalling
he/she/it has been metalling
we have been metalling
you have been metalling
they have been metalling

Future Perfect Continuous
I will have been metalling
you will have been metalling
he/she/it will have been metalling
we will have been metalling
you will have been metalling
they will have been metalling

Past Perfect Continuous
I had been metalling
you had been metalling
he/she/it had been metalling
we had been metalling
you had been metalling
they had been metalling

Conditional
I would metal
you would metal
he/she/it would metal
we would metal
you would metal
they would metal

Past Conditional
I would have metalled
you would have metalled
he/she/it would have metalled
we would have metalled
you would have metalled
they would have metalled

Thesaurus

Noun	1.	metal - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.metallic elementheavy metal - a metal of relatively high density (specific gravity greater than about 5) or of high relative atomic weight (especially one that is poisonous like mercury or lead)base metal - a metal that is common and not considered precious; "lead, iron, copper, tin, and zinc are base metals"chemical element, 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 matternoble metal - any metal that is resistant to corrosion or oxidationAl, aluminium, aluminum, atomic number 13 - a silvery ductile metallic element found primarily in bauxiteAm, americium, atomic number 95 - a radioactive transuranic metallic element; discovered by bombarding uranium with helium atomsantimony, atomic number 51, Sb - a metallic element having four allotropic forms; used in a wide variety of alloys; found in stibniteatomic number 56, Ba, barium - a soft silvery metallic element of the alkali earth group; found in bariteatomic number 97, berkelium, Bk - a radioactive transuranic element; discovered by bombarding americium with heliumatomic number 4, Be, beryllium, glucinium - a light strong brittle grey toxic bivalent metallic elementatomic number 83, Bi, bismuth - a heavy brittle diamagnetic trivalent metallic element (resembles arsenic and antimony chemically); usually recovered as a by-product from ores of other metalsatomic number 48, cadmium, Cd - a soft bluish-white ductile malleable toxic bivalent metallic element; occurs in association with zinc oresatomic number 20, Ca, calcium - a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animalsatomic number 98, californium, Cf - a radioactive transuranic element; discovered by bombarding curium with alpha particlesatomic number 58, Ce, cerium - a ductile grey metallic element of the lanthanide series; used in lighter flints; the most abundant of the rare-earth groupatomic number 55, caesium, cesium, Cs - a soft silver-white ductile metallic element (liquid at normal temperatures); the most electropositive and alkaline metalatomic number 24, chromium, Cr - a hard brittle multivalent metallic element; resistant to corrosion and tarnishingatomic number 27, cobalt, Co - a hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutritionatomic number 29, copper, Cu - a ductile malleable reddish-brown corrosion-resistant diamagnetic metallic element; occurs in various minerals but is the only metal that occurs abundantly in large masses; used as an electrical and thermal conductoratomic number 96, curium, Cm - a radioactive transuranic metallic element; produced by bombarding plutonium with helium nucleiatomic number 66, Dy, dysprosium - a trivalent metallic element of the rare earth group; forms compounds that are highly magneticatomic number 99, einsteinium, Es, E - a radioactive transuranic element produced by bombarding plutonium with neutronsatomic number 68, Er, erbium - a trivalent metallic element of the rare earth group; occurs with yttriumatomic number 63, Eu, europium - a bivalent and trivalent metallic element of the rare earth groupatomic number 100, fermium, Fm - a radioactive transuranic metallic element produced by bombarding plutonium with neutronsatomic number 87, Fr, francium - a radioactive element of the alkali-metal group discovered as a disintegration product of actiniumatomic number 64, gadolinium, Gd - a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth groupatomic number 31, gallium, Ga - a rare silvery (usually trivalent) metallic element; brittle at low temperatures but liquid above room temperature; occurs in trace amounts in bauxite and zinc oresatomic number 72, hafnium, Hf - a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electronsatomic number 67, Ho, holmium - a trivalent metallic element of the rare earth group; occurs together with yttrium; forms highly magnetic compoundsatomic number 49, indium, In - a rare soft silvery metallic element; occurs in small quantities in sphalerite
	2.	metal - a mixture containing two or more metallic elements or metallic and nonmetallic elements usually fused together or dissolving into each other when molten; "brass is an alloy of zinc and copper"alloymixture - (chemistry) a substance consisting of two or more substances mixed together (not in fixed proportions and not with chemical bonding)heavy metal - a metal of relatively high density (specific gravity greater than about 5) or of high relative atomic weight (especially one that is poisonous like mercury or lead)18-karat gold - an alloy that contains 75 per cent gold22-karat gold - an alloy that contains 87 per cent goldoreide, oroide - alloy of copper and tin and zinc; used in imitation gold jewelryAlnico - trade name for an alloy used to make high-energy permanent magnets; contains aluminum and iron and nickel plus cobalt or copper or titaniumamalgam, dental amalgam - an alloy of mercury with another metal (usually silver) used by dentists to fill cavities in teeth; except for iron and platinum all metals dissolve in mercury and chemists refer to the resulting mercury mixtures as amalgamsfusible metal - an alloy with a low melting point and used as solder and in safety plugs and sprinkler fuseselectrum - an alloy of gold and silverpewter - any of various alloys of tin with small amounts of other metals (especially lead)pinchbeck - an alloy of copper and zinc that is used in cheap jewelry to imitate goldpot metal - an alloy of copper and lead used especially for making large potssolder - an alloy (usually of lead and tin) used when melted to join two metal surfaceswhite gold - a pale alloy of gold usually with platinum or nickel or palladiumtype metal - an alloy of tin and lead and antimony used to make printing typebearing metal, white metal - an alloy (often of lead or tin base) used for bearingsbabbitt, Babbitt metal - an alloy of tin with some copper and antimony; a lining for bearings that reduces frictionBritannia metal - an alloy similar to pewterCARBOLOY - [trademark] an alloy based on tungsten with cobalt or nickel as a binder; used in making metal-cutting toolssteel - an alloy of iron with small amounts of carbon; widely used in construction; mechanical properties can be varied over a wide rangecheoplastic metal - any alloy that fuses at low temperatures and can be used molding artificial teethcopper-base alloy - any alloy whose principal component is copperdental gold - an alloy of gold used in dentistryDuralumin - an aluminum-based alloyInconel - a nickel-base alloy with chromium and iron; used in gas-turbine bladesInvar - an alloy of iron and nickel having a low coefficient of thermal expansion; used in tuning forks and measuring tapes and other instrumentsnickel alloy, nickel-base alloy - an alloy whose main constituent is nickelGerman silver, nickel silver - a silver-white alloy containing copper and zinc and nickelpyrophoric alloy - an alloy that emits sparks when struck or scratched with steel; used in lighter flintsshot metal - an alloy that is 98% lead and 2% arsenic; used in making small shotprimary solid solution, solid solution - a homogeneous solid that can exist over a range of component chemicals; a constituent of alloys that is formed when atoms of an element are incorporated into the crystals of a metalStellite - ® a very hard alloy of cobalt and chromium with cobalt as the principal ingredient; used to make cutting tools and for surfaces subject to heavy wearsterling silver - a silver alloy with no more than 7.5% coppertambac, tombac, tombak - an alloy of copper and zinc (and sometimes arsenic) used to imitate gold in cheap jewelry and for gildingWood's alloy, Wood's metal - a fusible alloy that is half bismuth plus lead, tin, and cadmium; melts at about 160 degrees Fahrenheit
Verb	1.	metal - cover with metal coat, surface - put a coat on; cover the surface of; furnish with a surface; "coat the cake with chocolate"
Adj.	1.	metal - containing or made of or resembling or characteristic of a metal; "a metallic compound"; "metallic luster"; "the strange metallic note of the meadow lark, suggesting the clash of vibrant blades"- Ambrose Biercemetallicnonmetal, nonmetallic - not containing or resembling or characteristic of a metal; "nonmetallic elements"

metal

noun

Metals

Metal	Symbol
actinium	Ac
aluminium	Al
americium	Am
antimony	Sb
barium	Ba
berkelium	Bk
beryllium	Be
bismuth	Bi
cadmium	Cd
caesium or (U.S.) cesium	Cs
calcium	Ca
californium	Cf
cerium	Ce
chromium	Cr
cobalt	Co
copper	Cu
curium	Cm
dysprosium	Dy
einsteinium	Es
erbium	Er
europium	Eu
fermium	Fm
francium	Fr
gadolinium	Gd
gallium	Ga
germanium	Ge
gold	Au
hafnium	Hf
holmium	Ho
indium	In
iridium	Ir
iron	Fe
lanthanum	La
lawrencium	Lr
lead	Pb
lithium	Li
lutetium	Lu
magnesium	Mg
manganese	Mn
mendelevium	Md
mercury	Hg
molybdenum	Mo
neodymium	Nd
neptunium	Np
nickel	Ni
niobium	Nb
nobelium	No
osmium	Os
palladium	Pd
platinum	Pt
plutonium	Pu
polonium	Po
potassium	K
praseodymium	Pr
promethium	Pm
protactinium	Pa
radium	Ra
rhenium	Re
rhodium	Rh
rubidium	Rb
ruthenium	Ru
samarium	Sm
scandium	Sc
silver	Ag
sodium	Na
strontium	Sr
tantalum	Ta
technetium	Tc
terbium	Tb
thallium	Tl
thorium	Th
thulium	Tm
tin	Sn
titanium	Ti
tungsten or wolfram	W
uranium	U
vanadium	V
ytterbium	Yb
yttrium	Y
zinc	Zn
zirconium	Zr

Translations

金属金属的合金合金的

metal

(ˈmetl) noun, adjective1. (of) any of a group of substances, usually shiny, that can conduct heat and electricity and can be hammered into shape, or drawn out in sheets, bars etc. Gold, silver and iron are all metals. 金属（的） 2. (of) a combination of more than one of such substances. Brass is a metal made from copper and zinc. 合金（的） meˈtallic (-ˈtӕ-) adjective1. made of metal. a metallic element.金属制的2. like a metal (eg in appearance or sound). metallic blue; a metallic noise.象金属的

metal

→ 金属zhCN

metal

metal,

chemical elementelement,
in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compound can be decomposed into its constituent elements by means of a chemical reaction, but no further simplification can be achieved.
..... Click the link for more information. 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 ionion,
atom or group of atoms having a net electric charge. Positive and Negative Electric Charges

A neutral atom or group of atoms becomes an ion by gaining or losing one or more electrons or protons.
..... Click the link for more information. , and the ability to conduct heat and electricity. The metals comprise about two thirds of the known elements (see 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. ). Some metals, including copper, tin, iron, lead, gold, silver, and mercury, were known to the ancients; copper is probably the oldest known metal.

Physical Properties

Metals differ so widely in hardness, ductility (the potentiality of being drawn into wire), malleability, tensile strength, density, and melting point that a definite line of distinction between them and the 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. cannot be drawn. The hardest elemental metal is chromium; the softest, cesium. Copper, gold, platinum, and silver are especially ductile. Most metals are malleable; gold, silver, copper, tin, and aluminum are extremely so. Some metals exhibiting great tensile strength are copper, iron, and platinum. Three metals (lithium, potassium, and sodium) have densities of less than one gram per cubic centimeter at ordinary temperatures and are therefore lighter than water. Some heavy metals, beginning with the most dense, are osmium, iridium, platinum, gold, tungsten, uranium, tantalum, mercury, hafnium, lead, and silver.

For many industrial uses, the melting points of the metals are important. Tungsten fuses, or melts, only at extremely high temperatures (3,370&degC;.), while cesium has a melting point of 28.5&degC;. The best metallic conductor of electricity is silver. Copper, gold, and aluminum follow in the order named. All metals are relatively good conductors of heat; silver, copper, and aluminum are especially conductive. The radioactive metal uranium is used in reactor piles to generate steam and electric power. Plutonium, another radioactive element, is used in nuclear weapons and nuclear reactors as well as in pacemakers. Some of the radioactive metals not found in nature, e.g., fermium and seaborgium, are produced by nuclear bombardment.

Some elements, e.g., arsenic and antimony, exhibit both metallic and nonmetallic properties and are called metalloids. Furthermore, although all metals form crystals, this is also characteristic of certain nonmetals, e.g., carbon and sulfur.

Chemical Properties

Chemically, the metals differ from the nonmetals in that they form positive ions and basic oxides and hydroxides. Upon exposure to moist air, a great many undergo corrosion, i.e., enter into a chemical reaction; e.g., iron rusts when exposed to moist air, the oxygen of the atmosphere uniting with the metal to form the oxide of the metal. Aluminum and zinc do not appear to be affected, but in fact a thin coating of the oxide is formed almost at once, stopping further action and appearing unnoticeable because of its close resemblance to the metal. Tin, lead, and copper react slowly under ordinary conditions. Silver is affected by compounds such as sulfur dioxide and becomes tarnished when exposed to air containing them. The metals are combined with nonmetals in their salts, as in carbides, carbonates, chlorides, nitrates, phosphates, silicates, sulfides, and sulfates.

The Electromotive Series

On the basis of their ability to be oxidized, i.e., lose electrons, metals can be arranged in a list called the electromotive serieselectromotive series,
list of metals whose order indicates the relative tendency to be oxidized, or to give up electrons (see oxidation and reduction); the list also includes the gas hydrogen. The electromotive series begins with the metal most easily oxidized, i.e.
..... Click the link for more information. , or replacement series. Metals toward the beginning of the series, like cesium and lithium, are more readily oxidized than those toward the end, like silver and gold. In general, a metal will replace any other metal, or hydrogen, in a compound that it precedes in the series, and under ordinary circumstances it will be replaced by any metal, or hydrogen, that it follows.

Metals in the Periodic Table

Metals fall into groups 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. determined by similar arrangements of their orbital electronselectron,
elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the basic constituents of matter.
..... Click the link for more information. and a consequent similarity in chemical properties. Groups of similar metals include the alkali metalsalkali metals,
metals found in Group 1 of the periodic table. Compared to other metals they are soft and have low melting points and densities. Alkali metals are powerful reducing agents and form univalent compounds.
..... Click the link for more information. (Group 1 in the periodic table), the alkaline-earth metalsalkaline-earth metals,
metals constituting Group 2 of the periodic table. Generally, they are softer than most other metals, react readily with water (especially when heated), and are powerful reducing agents, but they are exceeded in each of these properties by the
..... Click the link for more information. (Group 2 in the periodic table), and the rare-earth metalsrare-earth metals,
in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, which is not found in nature, is not usually considered a rare-earth metal.
..... Click the link for more information. (the lanthanidelanthanide series,
a series of metallic elements, included in the rare-earth metals, in Group 3 of the periodic table. Members of the series are often called lanthanides, although lanthanum (atomic number 57) is not always considered a member of the series.
..... Click the link for more information. and actinide seriesactinide series,
a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a member of the series.
..... Click the link for more information. of Group 3). Most metals other than the alkali metals and the alkaline earth metals are called transition metals (see transition elementstransition elements
or transition metals,
in chemistry, group of elements characterized by the filling of an inner d electron orbital as atomic number increases.
..... Click the link for more information. ). The oxidation states, or valencevalence,
combining capacity of an atom expressed as the number of single bonds the atom can form or the number of electrons an element gives up or accepts when reacting to form a compound.
..... Click the link for more information. , of the metal ions vary from +1 for the alkali metals to as much as +7 for some transition metals.

Sources and Uses

Although a few metals occur uncombined in nature, the great majority are found combined in their oresore,
metal-bearing mineral mass that can be profitably mined. Nearly all rock deposits contain some metallic minerals, but in many cases the concentration of metal is too low to justify mining the ore.
..... Click the link for more information. . The separation of metals from their ores is called extractive metallurgymetallurgy
, science and technology of metals and their alloys. Modern metallurgical research is concerned with the preparation of radioactive metals, with obtaining metals economically from low-grade ores, with obtaining and refining rare metals hitherto not used, and with the
..... Click the link for more information. . Metals are mixed with each other in definite amounts to form alloysalloy
[O. Fr.,=combine], substance with metallic properties that consists of a metal fused with one or more metals or nonmetals. Alloys may be a homogeneous solid solution, a heterogeneous mixture of tiny crystals, a true chemical compound, or a mixture of these.
..... Click the link for more information. ; a mixture of mercury and another metal is called an amalgamamalgam
, alloy containing mercury. The alloy may be liquid or solid, depending on the proportion of mercury, although all naturally occurring amalgams, i.e., those of gold and silver, are solid. Amalgams are widely used.
..... Click the link for more information. . Bronzebronze,
in metallurgy, alloy of copper, tin, zinc, phosphorus, and sometimes small amounts of other elements. Bronzes are harder than brasses. Most are produced by melting the copper and adding the desired amounts of tin, zinc, and other substances.
..... Click the link for more information. is an alloy of copper and tin, and brassbrass,
alloy having copper (55%–90%) and zinc (10%–45%) as its essential components. The properties of brass vary with the proportion of copper and zinc and with the addition of small amounts of other elements, such as aluminum, lead, tin, or nickel.
..... Click the link for more information. contains copper and zinc. Steelsteel,
alloy of iron, carbon, and small proportions of other elements. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese; steelmaking involves the removal of these impurities, known as slag, and the addition of desirable alloying elements.
..... Click the link for more information. is an alloy of iron and other metals with carbon added for hardness.

Since metals form positive ions readily, i.e., they donate their orbital electrons, they are used in chemistry as reducing agents (see oxidation and reductionoxidation and reduction,
complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation
..... Click the link for more information. ). Finely divided metals or their oxides are often used as surface catalystscatalyst,
substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis.
..... Click the link for more information. . Iron and iron oxides catalyze the conversion of hydrogen and nitrogen to ammonia in the Haber processHaber process
, commercial process for the synthesis of ammonia, NH₃. Pure hydrogen and nitrogen gases are mixed in the appropriate proportion, heated to between 450&degC; and 600&degC;, compressed to about 1,000 atmospheres pressure, and passed over a catalyst.
..... Click the link for more information. . Finely divided catalytic platinum or nickel is used in the hydrogenationhydrogenation
, chemical reaction of a substance with molecular hydrogen, usually in the presence of a catalyst. A common hydrogenation is the hardening of animal fats or vegetable oils to make them solid at room temperature and improve their stability.
..... Click the link for more information. of unsaturated oils. Metal ions orient electron-rich groups called ligandsligand
, charged or uncharged molecule with one or more unshared pairs of electrons that can attach to a central metallic atom or ion to form an aggregate known as a complex ion (see chemical bond). Some ligands that share electrons with metals form very stable complexes.
..... Click the link for more information. around themselves, forming complex ionscomplex ion,
charged molecular aggregate (see ion), consisting of a metallic atom or ion to which is attached one or more electron-donating molecules. In some complex ions, such as sulfate, SO₄⁻²
..... Click the link for more information. . Metal ions are important in many biological functions, including enzymeenzyme,
biological catalyst. The term enzyme comes from zymosis, the Greek word for fermentation, a process accomplished by yeast cells and long known to the brewing industry, which occupied the attention of many 19th-century chemists.
..... Click the link for more information. and coenzymecoenzyme
, any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a particular enzyme or exist freely in solution, but in either case it participates intimately in
..... Click the link for more information. action, nucleic acidnucleic acid,
any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replication of hereditary information and in the expression of this information through protein synthesis.
..... Click the link for more information. synthesis, and transport across membranes.

For the uses of specific metals, see separate articles.

metal

In astronomy, any element heavier than helium; the most abundant metals are oxygen, carbon, and nitrogen.

Metal

Any of a class of elementary substances which are crystalline when solid and characterized by opacity, ductility and conductivity; mined in a form called “ore” and manufactured to specific applications.

aluminum

A lightweight metal which is malleable and nonmagnetic and has good conductivity; it is a good reflector of heat and light and is resistant to oxidation; it is often anodized for better corrosion resistance, color and surface hardness.

brass

Any copper alloy having zinc as the principal alloying element, but often with small quantities of other elements.

bronze

An alloy of copper and tin, bronze in color, having a substantial admixture of copper to modify the properties of the principal element, such as aluminum bronze and magnesium bronze.

cast iron

A hard, nonmalleable iron alloy containing carbon and silicon, which is poured into a sand mold and then machined to a desired architectural shape.

copper

A metal with good electrical conductivity, used for roofing, flashing, hardware and plumbing applications; when exposed to air, copper oxidizes and develops a greenish “patina” that halts corrosion.

ferrous metal

A metal in which iron is the principal element.

iron

A metallic element found in the earth’s crust, consisting of a malleable, ductile, magnetic substance from which pig iron and steel are manufactured.

lead

A soft, malleable, heavy metal that has a low melting point and a high coefficient of thermal expansion; very easy to cut and work.

stainless steel

A high-strength, tough steel alloy; contains chromium with nickel as an additional alloying element and is highly resistant to corrosion and rust.

steel

A hard and malleable metal when heated; produced by melting and refining it according to the carbon content; used for structural shapes due to its alloy of iron and carbon which has a malleable high tensile strength.

tin

A lustrous white, soft, and malleable metal having a low melting point; relatively unaffected by exposure to air; used for making alloys and solder, and in coating sheet metal.

weathering steel

A high-strength, low-alloy steel that forms an oxide coating when exposed to rain or moisture, which adheres to the base metal and protects it from further corrosion.

wrought iron

A commercially pure iron of fibrous nature, valued for its corrosion resistance and ductility; used for water pipes, water tank plates, rivets, and other forged work.

zinc

A hard bluish-white metal, brittle at normal temperatures, very malleable and ductile when heated; not subject to corrosion; used for galvanizing sheet steel and iron in various metal alloys.

What does it mean when you dream about metal?

Metals are hard but malleable, a potent symbol of strength and character. Metals can also be cold and, because of their association with technology, represent the inhuman side of our society.

metal

[′med·əl] (astronomy) In stellar spectroscopy, any element heavier than helium. (materials) An opaque crystalline material usually of high strength with good electrical and thermal conductivities, ductility, and reflectivity; properties are related to the structure, in which the positively charged ions are bonded through a field of free electrons which surrounds them forming a close-packed structure.

Metal

An electropositive chemical element. Physically, a metal atom in the ground state contains a partially filled band with an empty state close to an occupied state. Chemically, upon going into solution a metal atom releases an electron to become a positive ion. Consequently in biotic systems metal atoms function prominently in ionic transport and electron exchange. In bulk a metal has a high melting point and a correspondingly high boiling temperature; except for mercury, metals are solid at standard conditions. Direct observation shows a metal to be relatively dense, malleable, ductile, cohesive, highly conductive both electrically and thermally, and lustrous. When crystals of the elements are classified along a scale from plastic to brittle, metals fall toward the plastic end. Furthermore, molten metals mixed with each other over wide ranges of proportions form, upon slowly cooling, homogeneous close-packed crystals. In contrast, a metal mixed with a nonmetal completely combines into a homogeneous crystal only in one or a few discrete stoichiometric proportions.

metal

1. a. any of a number of chemical elements, such as iron or copper, that are often lustrous ductile solids, have basic oxides, form positive ions, and are good conductors of heat and electricity b. an alloy, such as brass or steel, containing one or more of these elements 2. the substance of glass in a molten state or as the finished product 3. short for road metal4. Astronomy any element heavier than helium 5. the rails of a railway

METAL

(1)Mega-Extensive Telecommunications Applications Language.BBS language for PRODOS 8 on Apple II.

METAL

(2)The syntax-definition formalism of the Mentor system.Metal specifications are compiled to specifications for ascanner/parser generator such as Lex/Yacc. "Metal: AFormalism to Specify Formalisms", G. Kahn et al, Sci CompProg 3:151-188 (1983).

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bare metal

put the pedal to the metal

pedal to the metal

with the pedal to the metal

metal

put the pedal to the metal

put the pedal to the metal

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keep/put the ˌpedal to the ˈmetal

put the pedal to the metal

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Physical Properties

Chemical Properties

The Electromotive Series

Metals in the Periodic Table

Sources and Uses

metal

Metal

aluminum

brass

bronze

cast iron

copper

ferrous metal

iron

lead

stainless steel

steel

tin

weathering steel

wrought iron

zinc

What does it mean when you dream about metal?

metal

Metal

metal

METAL

METAL

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met·al (M),

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Patient discussion about metal

METAL

metal

Synonyms for metal

noun any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc

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noun a mixture containing two or more metallic elements or metallic and nonmetallic elements usually fused together or dissolving into each other when molten

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verb cover with metal

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adj containing or made of or resembling or characteristic of a metal

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