Avogadro s hypothesis

In terms of moles, Avogadro s hypothesis can be stated The same volume is occupied by one mole of any gas at a given temperature and pressure. The number of molecules in one mole is known as the Avogadro number constant. ... 

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 ... 

Avogadro s Hypothesis States that Equal volumes of different gases at the same pressure and temperature contain the same number of molecules. Hence, the volume occupied by any gas whose mass is numerically equal to its molecular weight is a constant quantity. 

This calculation of the proportions by partial pressure can be converted to proportions by weight, by multiplying each pressure by the molecular mass (Avogadro s hypothesis), to give ... 

The importance of Avogadro s Hypothesis is that it furnishes a basis for weighing molecules. Two equal volumes of gas (at the same temperature and pressure) are weighed. If we assume these two volumes contain identical numbers of molecules, then we must also conclude that the gas that weighs more must have heavier molecules. Furthermore, the ratio of the weights of the molecules must be exactly the ratio of the weights of the two gas samples. 

These simple, integer volume ratios confirm the usefulness of the interpretation that equal volumes contain equal numbers of molecules. This proposal was first made in 1811 by an Italian scientist, Amadeo Avogadro hence it is called Avogadro s Hypothesis. It has been used successfully in explaining the properties of gases for a century and a half. 

Avogadro s Hypothesis Equal volumes of gases, measured at the same temperature and pressure, contain equal numbers of molecules. 

Finally, we discover that exactly two volumes of nitric oxide combine with one volume of oxygen and that exactly two volumes of nitrogen dioxide are formed. According to Avogadro s Hypothesis, this indicates that... 

From these data alone and Avogadro s Hypothesis, how many molecules of hydrogen combine with one molecule of nitrogen How many molecules of ammonia are produced from one molecule of nitrogen ... 

Avogadro s Hypothesis provides a method for identifying the molecules present in a gas. Also, it explains why the volumes of gases that react with each other are in the same simple ratio as are the moles in the balanced equation. The importance of these results makes the explana-... 

The kinetic theory is based upon the premise that if two gases are at the same temperature, the molecules of the gases have the same average kinetic energy. The ability of this kinetic theory to explain Avogadro s Hypothesis is one of its most important successes. 

We may state Avogadro s Hypothesis in this form If two gases at the same temperature have the same number of particles in a given volume, they must exert the same pressure. Yet, as re-... 

Avogadro s Hypothesis can be shown quite readily in an approximate way. The kinetic energy of a moving particle is expressed by the equation... 

Avogadro s Hypothesis is consistent with the kinetic theory. Therefore a perfect gas follows Avogadro s Hypothesis. At one atmosphere pressure and 0°C, one mole (6.02 X 10 molecules) of a perfect gas occupies 22.414 liters. How closely real gases approximate a perfect gas at one atmosphere pressure and 0°C is shown by measur-... 

Regularities observed in the behavior of gases have contributed much to our understanding of the structure of matter. One of the most important regularities is Avogadro s Hypothesis Equal volumes of gases contain equal numbers of particles (at the same pressure and temperature). This relationship is valuable in the determination of molecular formulas—these formulas must be known before we can understand chemical bonding. 

At the University of St. Petersburg (now Leningrad), he distinguished himself in science and mathematics and earned the doctorate with a thesis on a subject that remains of current interest, The Union of Alcohol and Water." Subsequent studies in France and Germany permitted him to attend the 1858 Karlsruhe (Germany) conference at which Avogadro s Hypothesis was heatedly debated. Later, he visited the oil fields of Pennsylvania to see the first oil well. Upon his return to Russia, he developed a new commercial distillation process. 

Step II. By reaction (79), 1 mole of S02 reacts with mole of 02. By Avogadro s Hypothesis, 1 liter of S02 reacts with liter of 02 (if they are at the same temperature and pressure). Hence 1.00 X 105 liters of S02 react with 1(1.00 X 105) liters of 02 if both S02 and 02 are pure and measured at 500°C and one atmosphere. 

As current is passed through the cells shown in Figure 14-2, the oxygen produced in the first cell is collected and its volume is compared with the volume of chlorine produced in the center cell (the volumes being compared at identical temperatures and pressures). The volume of chlorine is found to be exactly double that of oxygen. Applying Avogadro s Hypothesis, explain how this result shows that electricity can count atoms. 

This returns us to the problem of the determination of molecular weight. Avogadro s Hypothesis provides one of the convenient ways of measuring molecular weight if the substance can be vaporized. 

Suppose such a vapor-density measurement shows that a given volume of ethanol at 100°C and one atmosphere weighs 1.5 times as much as the same volume of oxygen gas at 100°C and one atmosphere. Since equal volumes contain equal numbers of molecules at the same temperature and pressure (Avogadro s Hypothesis), one molecule of the unknown gas must weigh 1.5 times the weight of a molecule of 02. Therefore,... 

Kelvin temperature scale, 58 Ketones, 334 Kerosene. 231, 341 Kilo, 40 Kilocalorie, 40 Kinetic energy, 53, 114 billiard ball analogy, 6, 114 distribution, 130, 131 formula for, 59 of a moving particle, 59 relation to temperature, 56, 131 Kinetic theory, 49, 52, 53 and Avogadro s Hypothesis, 58 review, 61... 

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