Avogadros Law

Sec also Avogadro Law Boyle-Charles Law Boyle s Law Characteristic Equation and Combustion (Fuels). 

Conversely, suppose that we know the equation H2 + Clj - 2HC1. Then, according to the Avogadro law, the measured relative volumes of gases can be predicted from the relative numbers of molecules reacting and produced. 

It follows, then, from the Avogadro law that 22.4 liters (sc) of any other gas contains Nj molecules. Hence, the mass in grams of 22.4... 

Observe that the number of moles of gas is the same for all gases occupying the same volume at the same temperature and pressure, (merely a statement of the Avogadro law). But the mass of gas in this volume differs for different gases. The number of moles, n, is given by... 

Avogadro law. Given the following gaseous reactions at the same T and P, involving the elements E, F and the compounds G, H ... 

Eventually, Avogadro was shown to be correct, and today we call his hypothesis a law and write it in the form V = kn when P and T are held constant. We also write Avogadros law in the form To say, however, that equal volumes of gases at the same pressure and temperature contain an equal number of gas particles does not tell us how many gas particles there are. Certainly in the nineteenth century nobody knew of any way to count atoms... 

The properties of hydrocarbon gases are relatively simple since the parameters of pressure, volume and temperature (PVT) can be related by a single equation. The basis for this equation is an adaptation of a combination of the classical laws of Boyle, Charles and Avogadro. 

The behavior of all gases that obey the laws of Boyle and Charles, and Avogadro s hypothesis, can be expressed by the ideal gas equation ... 

In process engineering, moles are used extensively in performing (lie calculations. A mole is defined as that mass of a substance that is numen cally equal to its molecular weight. Avogadro s Law states that identical volumes of gas at the same temperature and pressure contain equal numbers of molecules for each gas. It can be reasoned that these identical volumes will have a weight proportional to the molecular weight of the gas. If the mass is expressed as... 

Avogadro s Law, 16 Axial compressor, 13, 14 application range, 14, 226 balance piston, 252... 

According to Avogadro s law, equal volumes of all gases under similar conditions contain the same number of molecules. Consequently the weights of equal volumes or the densities of gases will represent the ratio of their molecular weights. If the densities are compared with hydrogen as the unit, the ratio... 

Avogadro states that equal volumes of all gases, under the same conditions of pressure and temperature, contain the same number of molecules. This law is very important and is applied in many compressor calculations. 

We can evaluate the constant (kik2k3) in this equation by taking advantage of Avogadro s law, which states that equal volumes of all gases at the same temperature and pressure contain the same number of moles. For this law to hold, the constant must be the same for all gases. Ordinarily it is represented by the symbol R. Both sides of the equation are multiplied by P to give the ideal gas law... 

Avogadro s law, referred to on page 107, was proposed in 1811 by an Italian physicist at the University of Turin with the improbable name of Lorenzo Romano Amadeo Carlo Avogadro di Quarequa e di Cerreto (1776-1856). 

Avogadro suggested this relationship to explain the law of combining volumes. Today it seems obvious. For example, in the reaction... 

Stanislao Cannizzaro, professor of chemistry at f the University of Genoa. At a conference held in I Karlsruhe in 1860, he persuaded the chemistry community of the validity of Avogadro s law and showed how it could be used to determine molar and atomic masses, i The quantity now called "Avogadro s number (6.02 x 10 /mol) was first estimated in = 1865, nine years after Avogadro died. Not until... 

Atomic velocity distribution, 130,131 Atomic volume, 94, 98 alkali metals, 94 halogens, 97 inert gases, 91 third-row elements, 101 Atomic weight, 33 table, inside back cover Atoms, 21 conservation of, 40 electrical nature of, 236 measuring dimensions of, 245 Avogadro, Amadeo hypothesis, 25, 52 hypothesis and kinetic theory, 58 law, 25 number, 33 Azo dyes, 344... 

Kinetic theory A theory of matter based on the mathematical description of the relationship between pressures, volumes, and temperatures of gases (PVT phenomena). This relationship is summarized in the laws of Boyle s law, Charle s law, and Avogadro s law. 

Avogadro s principle rather than law, because it is based not on observation alone but also on a model of matter—namely that matter consists of molecules. Even though there is no longer any doubt that matter consists of atoms and molecules, it remains a principle rather than a law. 

Significance of the Faraday s laws, e= F/N relationship between the Faraday, Avogadro s number and the charge on the electron Besides the practical applications so far described, Faraday s laws have an important significance in so far as theoretical interest goes. The laws have introduced the concept of atomic nature of electricity. 

If no side reactions occur at the electrode that would participate in the overall current flow, then the Faraday law can be used not only to measure the charge passed (i.e. in coulometres see Section 5.5.4) but also to define the units of electric current and even to determine Avogadro s constant. 

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