The atomic number uniquely identifies a chemical element.

Each element has a specific set of chemical properties as a consequence of the number of electrons present in the neutral atom, which is Z ( the atomic number ).

Hence it is the atomic number alone that determines the chemical properties of an element ; and it is for this reason that an element can be defined as consisting of any mixture of atoms with a given atomic number.

Argon ( ) is a chemical element with symbol Ar and atomic number 18.

The name " argon " is derived from the Greek word αργον meaning " lazy " or " the inactive one ", a reference to the fact that the element undergoes almost no chemical reactions.

Arsenic ( ) is a chemical element with symbol As and atomic number 33.

Antimony ( or ; ) is a toxic chemical element with symbol Sb and atomic number 51.

Actinium ( ) is a radioactive chemical element with symbol Ac and atomic number 89, which was discovered in 1899.

Americium ( ) is a transuranic radioactive chemical element that has the symbol Am and atomic number 95.

Astatine ( or ) is a radioactive chemical element with the chemical symbol At and atomic number 85.

An atom is classified according to the number of protons and neutrons in its nucleus: the number of protons determines the chemical element, and the number of neutrons determines the isotope of the element.

The electrons determine the chemical properties of an element, and strongly influence an atom's magnetic properties.

He proposed that each element consists of atoms of a single, unique type, and that these atoms can join together to form chemical compounds.

* Americium, a chemical element

* Of or relating to the Atom, the smallest particle of a chemical element that retains its chemical properties

of atoms, in the modern sense of the basic unit of a chemical element.

* 1982 – The synthetic chemical element Meitnerium, atomic number 109, is first synthesized at the Gesellschaft für Schwerionenforschung in Darmstadt, Germany.

This text clarified the concept of an element as a substance that could not be broken down by any known method of chemical analysis, and presented Lavoisier's theory of the formation of chemical compounds from elements.

Allotropes are different structural forms of the same element and can exhibit quite different physical properties and chemical behaviours.

* Gold, a chemical element with the symbol Au

The drug's chemical name is listed, since most states require feed processors to use this name instead of the trade name on the feed tag.

In some instances, the trade name is shown in parentheses following the chemical name.

Even here there is room for some variation, for metal surfaces vary in smoothness, absorptive capacity, and chemical reactivity.

As is well known, detergent actives belong to the chemical class consisting of moderately high molecular weight and highly polar molecules which exhibit the property of forming micelles in solution.

On chemical grounds it seems most likely that iodide is first converted to Af and then to Af as the active iodinating species.

The chemical nature of the iodocompounds is discussed below ( pp. 76 et seq. ).

It is therefore necessary to consider the properties of pituitary TSH if the fragmentary chemical information about blood TSH is to be discussed rationally.

The importance of knowing in what chemical forms the hormone may exist is accentuated by the recent observation that there exists an abnormally long-acting TSH in blood drawn from many thyrotoxic patients ( Adams, 1958 ).

Whether this abnormal TSH differs chemically from pituitary TSH, or is, alternatively, normal TSH with its period of effectiveness modified by some other blood constituent, cannot be decided without chemical study of the activity in the blood of these patients and a comparison of the substance responsible for the blood activity with pituitary Aj.

The aim is to collect a very broad range of physical, chemical, morphological, and structural data for crystals on an encyclopedic scale and to seek all possible useful and revealing correlations of properties with internal structure.

The process in which the outcome of any one stage is known only statistically is also of interest, although for chemical reactor design it is not as important as the deterministic process.

It is a popular belief that alchemists made contributions to the " chemical " industries of the day — ore testing and refining, metalworking, production of gunpowder, ink, dyes, paints, cosmetics, leather tanning, ceramics, glass manufacture, preparation of extracts, liquors, and so on ( it seems that the preparation of aqua vitae, the " water of life ", was a fairly popular " experiment " among European alchemists ).

Experiments have been conducted to attempt the synthesis of ununennium ( Uue ), which is likely to be the next member of the group, but they have all met with failure .< ref name =" link "> However, ununennium may not be an alkali metal due to relativistic effects, which are predicted to have a large influence on the chemical properties of superheavy elements.

The number of electrons in each element's electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior.

Hypersonic flow is characterized by high temperature flow behind a shock wave, viscous interaction, and chemical dissociation of gas.

A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms.

Chemical reactions are usually characterized by a chemical change, and they yield one or more products, which usually have properties different from the reactants.

Reactions can also be characterized by the internal energy which takes into account changes in the entropy, volume and chemical potential.

The chemical properties of dubnium are characterized only partly.

The chemical bonding in these compounds is characterized as predominantly covalent and thus they are not thermodynamically stabilized by a high ionic-lattice energy.

It is characterized by its high chemical and physical resistivity.

Organic compounds were traditionally characterized by a variety of chemical tests, called " wet methods ", but such tests have been largely displaced by spectroscopic or other computer-intensive methods of analysis.

The chemical properties of rutherfordium are characterized only partly.

The chemical name for vitamin C, ascorbic acid, is derived from the Latin name of scurvy, scorbutus, which also provides the adjective scorbutic (" of, characterized by or having to do with scurvy ").

Multiple chemical sensitivity ( MCS ) is a chronic medical condition characterized by symptoms that the affected person attributes to low-level chemical exposure.

The Russian chemist and science historian Lev Chugaev has characterized him as " a chemist of genius, first-class physicist, a fruitful researcher in the fields of hydrodynamics, meteorology, geology, certain branches of chemical technology ( explosives, petroleum, and fuels, for example ) and other disciplines adjacent to chemistry and physics, a thorough expert of chemical industry and industry in general, and an original thinker in the field of economy.

Chemisorption is characterized by chemical specificity.

They proposed the term to describe chemical signals from conspecifics that elicit innate behaviors soon after the German Biochemist Adolf Butenandt characterized the first such chemical, bombykol ( a chemically well-characterized pheromone released by the female silkworm to attract mates ).

Intensive farming or intensive agriculture is an agricultural production system characterized by a low fallow ratio and the high use of inputs such as capital, labour, or heavy use of pesticides and chemical fertilizers relative to land area ..

Intensive farming or intensive agriculture is an agricultural production system characterized by the high inputs of capital, labour, or heavy usage of technologies such as pesticides and chemical fertilizers relative to land area.

Every instance of phase or chemical equilibrium is characterized by a constant.

Robert Gore was granted on April 27, 1976, for a porous form of polytetrafluoroethylene ( the chemical constituent of Teflon ) with a micro-structure characterized by nodes interconnected by fibrils.

They are characterized by 1. a fairly homogeneous composition ; 2. an extremely low content of water and other volatiles ; 3. an abundant lechatelierite ; 4. a general lack of microscopic crystals known as microlites and chemical relation to the local bedrock or local sediments ; and 5. their distribution within geographically extensive strewnfields.

The Swager main chain crown ether PTs were prepared by chemical coupling and characterized by absorbance spectroscopy.

* Environmental illness ( multiple chemical sensitivity ), a chronic medical condition characterized by symptoms that the affected person attributes to exposure to low levels of chemicals