Avogadro, Amedeo Hypothesis

Gay-Lussac did not theorize on his experimental findings, but in 1811 shortly after their publication the Italian chemist Amedeo Avogadro used them to formulate an important postulate since known as Avogadro s hypothesis ... 

Mendeleev also attended the 1860 Karlsruhe Congress, the first international chemistry conference. Many of the leading chemists of the day were in attendance, and one of the central questions addressed was the appropriate method for calculating atomic weight. Different chemists used different systems, leading to widespread confusion over everything from nomenclature to chemical formulas. Mendeleev heard the Itafian chemist Stanislao Cannizzaro present Amedeo Avogadro s hypothesis that equal vol-tunes of gas under equal temperature and pressure contained equal numbers of molecules. 

The first to point out the necessity of this assumption that, in gases, equal numbers of particles take up equal volumes, was the Italian chemist Amedeo Avogadro (1776-1856). The assumption, advanced in 1811, is therefore known as Avogadro s hypothesis. 

Three years later Amedeo Avogadro interpreted Gay-Lussac s observation by proposing what is now known as Avogadro s hypothesis Equal volumes of gases at the same temperature and pressure contain equal numbers of molecules. For example, 22.4 L of any gas at 0 °C and 1 atm contain 6.02 X 10 gas molecules (that is, 1 mol), as depicted inT FIGURE 10.10. 

Avogadro, Amedeo (1776-1856) Italian chemist and physicist, in 1811 he published his hypothesis (seeAvoGADRo s law), which provided a method of calculating molecular weights from vapour densities. The importance of the work remained unrecognized, however, until championed by Stanislao Cannizzaro (1826-1910) in 1860. 

Avogadro s law (Avogadro s hypothesis) The principle that equal volumes of all gases at the same temperature and pressure contain equal numbers of molecules. It is often called Avogadro s hypothesis because it was first proposed by the Italian chemist and physicist Amedeo Avogadro (1776-1856) in 1811. It is strictly true only for ideal gases. 

Such a simple empirical law as this called for a simple theoretical interpretation, and in 1811 Amedeo Avogadro (1776-1856), professor of physics in the University of Turin, proposed a hypothesis to explain the law. Avogadro s hypothesis was that equal numbers of molecules are contained in equal volumes of all dilute gases under the same conditions. This hypothesis has been thoroughly verified to within the accuracy of approximation of real gases to ideal behavior, and it is now called a law— Avogadro s law. ... 

Amedeo Avogadro s hypothesis that equal volumes of gases at the same temperature and pressure contain the same numher of molecules provided the conceptual foundation on which the mole concept and Avogadro s numher were huilt. 

In 1860 Stanislao Cannizzaro (Hshowed that the earlier hypothesis of Amedeo Avogadro (1811, ii... 

While most beginning chemistry students associate the name of Avogadro with moles and Avogadro s number, Amedeo Avogadro s principal contribution to the chemical sciences is the hypothesis that, at equal temperatures and pressures, equal volumes of gas contain equal numbers of particles. This work made the determination of several atomic and molecular masses possible. In other words, the volume of a gas is directly proportional to the number of gas molecules, as long as temperature and pressure are held constant. 

Amedeo Avogadro developed the hypothesis that equal volumes of different gases contain an equal number of molecules, if the gases are at the same temperature and pressure. The proportionality between volume and number of moles is called Avagadro s Law, and the number of molecules in a mole is called Avagadro s Number. Both were posthumously named in his honor. 

In England, around the same time, John Dalton studied the masses of compounds as they reacted to produce products. After Dalton read about the similar work of other scientists, such as Lavoisier and the British scientist Joseph Priestley, he contacted Gay-Lussac. He described his results and hypotheses to Gay-Lussac. In 1808, both men published their theories. After examining the theories of Dalton and Gay-Lussac, an Italian scientist named Amedeo Avogadro formulated a hypothesis that combined their theories. 

In 1800, chemists did not know that the elementary gases were diatomic, and they wondered how two molecules of HCl were formed from one molecule of H and one of Cl. The law of combining volumes led Amedeo Avogadro (1776-1856) to postulate in 1811 a hypothesis that equal volumes of gases under like conditions of temperature and pressure contain equal numbers of molecules. The fact that molecules of hydrogen and chlorine had to be diatomic stemmed from this generalization. 

Lorenzo Romano Amedeo Carlo Avogadro, Conte di Quaregna e Ceretto was born in Turin, Italy in 1776 and was educated as a church lawyer. During the early 1800s, he studied mathematics and physics and was appointed to a professorship at the Royal College of Vercelli where he produced his hypothesis on gases. From 1820 untii his death, Avogadro was professor of physics at the University of Turin where he conducted research on eiectricity and the physicai properties of iiquids. 

The work of the Itahan scientist Amedeo Avogadro complemented the studies of Boyle, Charles, and Gay-Lussac. In 1811 he published a hypothesis stating that at the same temperature and pressure, equal volumes of different gases contain the same number of molecules (or atoms if the gas is monatomic). It follows that the volume of any given gas must be proportional to the number of moles of molecules present that is. 

In 1811, Amedeo Avogadro" (in full, Lorenzo Romano Amedeo Carlo Avo-gadro di Quaregua e di Cerreto, 1776-1856) used Gay-Lussac s, Dalton s, and others works to make his hypothesis equal volumes of gases (at same temperature and pressure) have equal numbers of molecules. Interestingly, this contribution was largely forgotten until resurrected by Cannizaro in 1858. ... 

The work of the Italian scientist Amedeo Avogadro complemented the studies of Boyle, Avogadro s name first appeared in Charles, and Gay-Lussac. In 1811 he published a hypothesis stating that at the same sertion3.2. 

Amedeo Avogadro (1776-1856) was an Italian physicist who made many early contributions to the concepts of molecular behaviour and relative molecular mass (formerly known as molecular weight) (Figure 1.48). His most critical contribution was making the distinction between atoms and molecules. His hypothesis was based on the careful experimental work by Gay-Lussac and John Dalton s atomic theory. He trained and practised as a lawyer, but later became Professor of Physics at Turin University. As a tribute to him, the number of particles in one mole of a substance is known as the Avogadro constant (formerly known as the Avogadro number). 

Amedeo Carlo Avogadro (1776-1856) was an Italian chemist, most noted for his contributions to the theory of molarity and molecular weight. In 1811, he declared the hypothesis of what we now call Avogadro s law Equal volumes of gases, at the same temperature and pressure, contain the same number of molecules. Hence, the gas laws of Boyle, Mariotte and Cay-Lussac in combination with Avogadro s Law can be generalized by the ideal gas law. The Avogadro constant Na, that is, the number of molecules in one mol is 6.022 x 10 mol is named in his honor. The numerical value of /Va was first estimated in 1865 by Johann Josef Loschmidt (1821-1895), an Austrian scientist. 

In 1811 Amedeo Avogadro (1776-1856) announced his hypothesis that under conditions of the same temperature and pressure, equal volumes of all gases contained equal number of molecules. This hypothesis greatly helped in... 

The extension of the hypothesis of Amedeo Avogadro (1776-1856) to dilute solutions proposed by Jacobus Henricus van t HoflF (1852-1911), opened a new direction for experimental research within inorganic chemistry. Piccini imderstood the importance of new theories, while, at the same time, he continued to pursue his favorite topic systematics. The problem that he found most interesting was to understand the isomerism of the green and violet salts of chromium [73] in the form of the sesquioxides, a problem that Werner had addressed with his coordination theory [74]. 

Amedeo Avogadro (1776-1856) was an Italian physicist. His famous hypothesis about gases was that at the same pressures and temperatures, equal volumes of gases contain equal numbers of particles. Chemists and physicists in Avogadro s time were still undecided about the existence of atoms and molecules. Without experimental evidence to support his hypothesis, Avogadro was pretty much ignored during his lifetime. 

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