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.

The field of chemistry uses analysis in at least three ways: to identify the components of a particular chemical compound ( qualitative analysis ), to identify the proportions of components in a mixture ( quantitative analysis ), and to break down chemical processes and examine chemical reactions between elements of matter.

Strictly speaking, a mixture of compounds, elements or compounds and elements is not a chemical substance, but it may be called a chemical.

Through a series of derivations, de Donder showed that if we consider a mixture of chemical species with the possibility of chemical reaction, it can be proven that the following relation holds:

The term concentration can be applied to any kind of chemical mixture, but most frequently it refers to solutes in solutions.

A chemical explosive may consist of either a chemically pure compound, such as nitroglycerin, or a mixture of a fuel and an oxidizer, such as black powder or grain dust and air.

The Fick's law is limiting case of the Maxwell-Stefan equations, when the mixture is extremely dilute and every chemical species is interacting only with the bulk mixture and not with other species.

Once ignited and burnt, the combustion products — hot gases — have more available thermal energy than the original compressed fuel-air mixture ( which had higher chemical energy ).

A helium-neon ( HeNe ) laser uses an electrical discharge in the helium-neon gas mixture, a Nd: YAG laser uses either light focused from a xenon flash lamp or diode lasers, and excimer lasers use a chemical reaction.

Bauxites are the chief aluminium ore, and are a heterogenous mixture of the hydroxide minerals diaspore, gibbsite, and bohmite ; they form in areas with a very high rate of chemical weathering ( mainly tropical conditions ).

Another set of important questions in chemistry concerns what kind of reactions can happen spontaneously and which properties are possible for a given chemical mixture.

The mantle of the mollusk deposits layers of calcium carbonate ( CaCO < sub > 3 </ sub >) in the form of the mineral aragonite or a mixture of aragonite and calcite ( polymorphs with the same chemical formula, but different crystal structures ) held together by an organic horn-like compound called conchiolin.

Other important variables include chemical composition, molecular weight and weight distribution, degree of branching and crystallinity, types of functionality, component concentration, dilution with solvents or plasticizers, and mixture with other materials to form composite systems.

In many cases, a commercial pesticide is itself a combination of several chemical agents, and thus the safe levels actually represent levels of the mixture.

Further processing by chemical separation is usually done by treating the ores with a mixture of hydrofluoric acid and sulfuric acid at over 90 ° C.

In chemical composition it may be considered as essentially an isomorphous mixture of pyrope and almandine, in the proportion of two parts pyrope to one part almandine.

For example, a mixture of lithium, hydrogen, and fluorine produced a specific impulse of 546 seconds ; the highest ever of any chemical rocket motor.

Soy sauce may be made either by fermentation or by hydrolysis ; some commercial sauces contain a mixture of fermented and chemical sauces.

The primer is a small charge of an impact-sensitive chemical mixture that can be located at the center of the case head ( centerfire ammunition ) or inside a rim ( rimfire ammunition ).

Using results from the chemical measurements, mineral models suggest that the soil could be a mixture of about 90 % iron-rich clay, about 10 % magnesium sulfate ( kieserite?

They comprise a mixture of diterpinoid resins and n-alkyl compounds.

Different compounds in the sample mixture travel different distances according to how strongly they interact with the stationary phase as compared to the mobile phase.

This paper is made of cellulose, a polar substance, and the compounds within the mixture travel farther if they are non-polar.

Commercial DDT is a mixture of several closely – related compounds.

Upon contact with air, it begins to tarnish by forming a complex mixture of compounds depending on the conditions.

A ternary mixture of Schiff base compounds resulted in a material that had a nematic range of 22 – 105 ° C.

Within a day, the mixture had turned pink in colour, and at the end of two weeks of continuous operation, Miller and Urey observed that as much as 10 – 15 % of the carbon within the system was now in the form of organic compounds.

One-step reactions among the mixture components can produce hydrogen cyanide ( HCN ), formaldehyde ( CH < sub > 2 </ sub > O ), and other active intermediate compounds ( acetylene, cyanoacetylene, etc.

Petroleum ( L. petroleum, from ( rock ) + ( oil )) or crude oil is a naturally occurring flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface.

Working in conjunction with Louis Daguerre, they experimented with silver compounds based on a Johann Heinrich Schultz discovery in 1816 that a silver and chalk mixture darkens when exposed to light.

It was discovered in 1803 by William Hyde Wollaston in one such ore, and named for the rose color of one of its chlorine compounds, produced after it reacted with the powerful acid mixture aqua regia.

The venom is a mixture of compounds ( neurotoxins, enzyme inhibitors, etc.

Real seedpod extract is an extremely complicated mixture of several hundred different compounds, including acetaldehyde, acetic acid, furan-2-carbaldehyde, hexanoic acid, 4-hydroxybenzaldehyde, 2-methoxy-4 -( prop-2-en-1-yl ) phenol, methyl 3-phenylprop-2-enoate, and 2-methylpropanoic acid.

Pottery vessels containing a mixture of mead, rice and other fruits along with organic compounds of fermentation were found in Northern China.

Natural rubber, also called India Rubber or Caoutchouc, is a mixture of organic compound polyisoprene and small amounts of other organic compounds as well as water.

Beeswax is a tough wax formed from a mixture of several compounds.

The dust particles were found to be primarily a mixture of carbon-hydrogen-oxygen-nitrogen ( CHON ) compounds common in the outer Solar System, and silicates, such as are found in terrestrial rocks.

There is a wide range of organic, or hydrocarbon, compounds in any given fuel mixture.

Oil shale and similar materials are sedimentary rocks containing kerogen, a complex mixture of high-molecular weight organic compounds, which yield synthetic crude oil when heated ( pyrolyzed ).

Any of these compounds serve the same role, reversibly forming a mixture of metal hydride compounds.

Tannin powder ( mixture of compounds ).

Free radical halogenation typically produces a mixture of compounds mono-or multihalogenated at various positions.