Avogadro Number? help please answer this for me:(?
Both Josef Loschmidt and Amedeo Avogadro contributed to our understanding of basic molecular numbers, sizes, and reaction ratios. Neither scientist discovered “Avogadro’s number” in the form we use it today (6.02 x 10 23). Still, there’s a controversy over the name. Research the contributions from these two scientists and read about how Avogadro’s number got its name. Briefly state what you think this number should be called, providing key details of each scientist’s contributions to this concept and a solid rationale for your case in naming the number.
- Anonymous7 years agoBest Answer
The Avogadro constant is named after the early 19th century Italian scientist Amedeo Avogadro, who in 1811 first proposed that the volume of a gas (at a given pressure and temperature) is proportional to the number of atoms or molecules regardless of the nature of the gas. The French physicist Jean Perrin in 1909 proposed naming the constant in honor of Avogadro. Perrin won the 1926 Nobel Prize in Physics, largely for his work in determining the Avogadro constant by several different methods.
The value of the Avogadro constant was first indicated by Johann Josef Loschmidt who in 1865 estimated the average diameter of the molecules in air by a method that is equivalent to calculating the number of particles in a given volume of gas. This latter value, the number density of particles in an ideal gas, is now called the Loschmidt constant in his honor, and is related to the Avogadro constant, NA, by
where p0 is the pressure, R is the gas constant and T0 is the absolute temperature. The connection with Loschmidt is the root of the symbol L sometimes used for the Avogadro constant, and German language literature may refer to both constants by the same name, distinguished only by the units of measurement.
Accurate determinations of Avogadro's number require the measurement of a single quantity on both the atomic and macroscopic scales using the same unit of measurement. This became possible for the first time when American physicist Robert Millikan measured the charge on an electron in 1910. The charge of a mole of electrons is the constant called the faraday and had been known since 1834 when Michael Faraday published his works on electrolysis. By dividing the charge on a mole of electrons by the charge on a single electron the value of Avogadro's number is obtained. Since 1910, newer calculations have more accurately determined the values for Faraday's constant and the elementary charge. (See below #Measurement)
Perrin originally proposed the name Avogadro's number (N) to refer to the number of molecules in one gram-molecule of oxygen (exactly 32g of oxygen, according to the definitions of the period), and this term is still widely used, especially in introductory works. The change in name to Avogadro constant (NA) came with the introduction of the mole as a base unit in the International System of Units (SI) in 1971, which recognized amount of substance as an independent dimension of measurement. With this recognition, the Avogadro constant was no longer a pure number, but had a unit of measurement, the reciprocal mole (mol−1).
While it is rare to use units of amount of substance other than the mole, the Avogadro constant can also be defined in units such as the pound mole (lb-mol) and the ounce mole (oz-mol).
NA = 2.73159757(14)×1026 (lb-mol)−1 = 1.707248479(85)×1025 (oz-mol)−1
 General role in scienceAvogadro's constant is a scaling factor between macroscopic and microscopic (atomic scale) observations of nature. As such, it provides the relation between other physical constants and properties. For example, it establishes a relationship between the gas constant R and the Boltzmann constant kB,Source(s): http://wikipedia.org/wiki/avodadro_constand. 10 credit
- 3 years ago
A mole is 6.02 x 10^23, so the answer is 2.Four x 10^18 molecules / (6.02 x 10^23 molecules/mole). If a mole is 10^23 and there are handiest 10^18 particles, then the reply must be lower than 1. BTW: that is one more example of unhealthy chemistry homework. Chemists don't ever use the specific value of Avogadro's quantity. That is seeing that we express amounts in grams, no longer atoms.
- Anonymous5 years ago
We might all have come across the number 6.0221415 × 1023 in our chemistry text books. It is called the Avogadro’s number in honor of the Italian scientist Avogadro who found it. In simple terms, it is referred to as a ‘mole’. A mole or Avogadro’s number is simply used by the chemists to measure the amount of a substance or count the particles of matter – atoms and molecules. Today Avogadro’s number(6.0221415 × 1023) has such a great importance that mole day is being celebrated every year by the chemists unofficially on 23rd October beginning from 6:02 AM to 6: 02 PM to make sense to Avogadro’s number.
We know that the nucleus of an atom makes up more than 99.9% of its mass. Electrons do not contribute anything to the mass of an atom which is measured in terms of atomic mass unit (amu). One amu is defined as 1/12th of the mass of one carbon atom (with 6 protons and 6 neutrons inside the nucleus). But as the chemists did not have a scale to measure different weights of different atoms, they wanted to find a relation between amu and grams. One amu was found to be equivalent to 1g/mol (or)
1 amu = 1/6.0221415× 1023 grams.