Avogadro, Amedeo Number

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. 

It s been found experimentally that this number of atoms, ions, molecules, or anything else in one mole is 6.022045x1 o23. For most purposes, three significant digits are sufficient, and 6.02x1 o23 will be used. This value was named in honor of Amedeo Avogadro after his death and it is referred to as Avogadro s number. 

This same number is called a mole. Mole is a counting word, just as dozen is a counting word. Although the word dozen makes everyone think of 12, the word mole makes chemists think of 6.02 x 1023. A mole is 6.02 x 1023. A mole of donuts is 6.02 x 1023 donuts. TWo moles of marbles is 2 x 6.02 x 1023 marbles. The number 6.02 x 1023 is called Avogadro s number, after Amedeo Avogadro, the Italian scientist who was instrumental in its development. Now look at the molar masses that you calculated above ... 

In chemistry, a mole is a certain number of particles, usually of atoms or molecules. Just as a dozen particles (abbreviated doz.) would be 12 of them, a mole of particles (abbreviated mol) is 6.022137 X 10 of them. This number, usually shortened to 6.02 X 10, is known as Avogadro s number in honor of Count Amedeo Avo-gadro (1776-1856), an Italian professor of chemistry and physics at the University of Turin who was the first person to distinguish in a useful way between atoms and molecules. It is such a huge number (more than 600 billion trillion) because atoms and molecules are so incredibly tiny that we must have huge numbers of them before we can do anything useful with them. 

Avogadro s number N—The number of molecules present in one mole of whatever the compound is always equal to 6.0229 X 10. It was named for the Italian physicist Amedeo Avogadro. 

What is a mole The mole, commonly abbreviated mol, is the SI base unit used to measure the amount of a substance. It is the number of representative particles, carbon atoms, in exactly 12 g of pure carbon-12. Through years of experimentation, it has been established that a mole of anything contains 6.022 136 7 X 10 representative particles. A representative particle is any kind of particle such as atoms, molecules, formula units, electrons, or ions. The number 6.022 136 7 X 10 is called Avogadro s number in honor of the Italian physicist and lawyer Amedeo Avogadro who, in 1811, determined the volume of one mole of a gas. In this book, Avogadro s number will be rounded to three significant figures—6.02 X 10. ... 

To add to this convenience, the number 602,000,000,000,000,000,000,000 is also given a name. It is called Avogadro s number, in honor of Amedeo Avogadro, a famous Italian chemist. So, if you are speaking about the total number of atoms in 1 mole of water molecules, you can simply say three times Avogadro s number, or 3 x (6.02 x 1023), which is 1.81 x 104 atoms. 

This number, often rounded off to 6.022 X lO, is called Avogadro s number in honor of Amedeo Avogadro (1776-1856), whose contributions to chemistry are discussed in Section 12-8. 

This number is caWeA Avogcidro s number, in honor of the Italian scientist Amedeo Avogadro. Generally, we round Avogadro s number to 6.022 X 10. Thus, just as one... 

This number is Avogadro s number. Amedeo Avogadro, a nineteenth-century scientist, conducted a series of experiments that provided the basis for the mole concept. 

The mole (abbreviated mol) is the SI unit for amount of substance. It is defined as the amount of a substance that contains the same number of entities as there are atoms in exactly 12 g of carbon-12. This number is called Avogadro s number, in honor of the 19 -century Italian physicist Amedeo Avogadro, and as you can tell from the definition, it is enormous ... 

Some people think that Amedeo Avogadro (1776-1856) determined the number of particles in a mole and that is why the quantity is known as Avogadro s number. In reafity Avogadro built a theoretical foundation for determining accurate atomic and molecular masses. The concept of a mole did not even exist in Avogadro s time. 

The number 6.0221367 x 10 is called Avogadro s number, in honor of the Italian physicist and lawyer Amedeo Avogadro, who, in 1811, determined the volume of 1 mol of a gas. In this book, Avogadro s number is rounded to three significant figures, 6.02 x 10. ... 

FIGURE 4.R.1 Amedeo Avogadro s caricature (drawn by the historian W. B. Jensen and reproduced here with his permission) and Avogadro s number. 

The word mole stands for a number — 6.022 x 10. It s commonly called Avogadro s number, named after Amedeo Avogadro, the scientist who laid the groundwork for the mole principle. 

Avogadro s number a-v9- ga-(i)droz- [Count Amedeo Avogadro] (1924) np. The number of atoms in exactly 12g of C ... 

Atomic mass units provide a relative scale for the masses of the elements. But because atoms have such small masses, no usable scale can be devised to weigh them in calibrated units of atomic mass units. In any real situation, we deal with macroscopic samples containing enormous numbers of atoms. It is convenient, therefore, to have a special unit to describe a very large number of atoms. The idea of a unit to denote a particular number of objects is not new. For example, the pair (2 items), the dozen (12 items), and the gross (144 items) are all commonly used. Chemists measure atoms and molecules in moles. In the SI system the mole (mol) is the amount of a substance that contains as many elementary entities (atoms, molecules, or other particles) as there are atoms in exactly 12 g (or 0.012 kg) of the carbon-12 isotope. The actual number of atoms in 12 g of carbon-12 is determined experimentally. This number is called Avogadro s number (Njf), in honor of the Itahan scientist Amedeo Avogadro. The currently accepted value is... 

In 1811, Italian physicist Amedeo Avogadro presented a theory in the Journal de Physique that the mass of one mole of a sample contains the same basic number of particles as in 12 grams of That number of atoms is called Avogadro s number or a mole of sample. 

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