The Avogadro constant

N is the Avogadro constant, and b is the effective bond length of bonds of the chain, such that = vb2, where is the mean-square end-to-end distance of the chain. 

The Avogadro constant is the number of particles contained in one mole of a substance. Its value is 6.02 x 1023 mob1 and its symbol is L. In one mole of the carbon-12 isotope, there are 6.02 x 1023 12C atoms. 

One mole of any element contains 6.022x 1023 atoms, the Avogadro constant. 

In these problems we use the Avogadro constant and the fact that one mole of atoms of an element has a weight in grams equal to its atomic mass. 

Now we can determine the mass per A1 atom, and a value for the Avogadro constant. 

This value is for one pair of vacancies. To obtain the molar quantity, we multiply AZZp above by NA, the Avogadro constant, to yield... 

The number of elementary entities in 1 mol is an experimentally determined quantity, and is called the Avogadro constant L, which has the value 6.022 x 1023 mol-1. The Avogadro constant is also (incorrectly) called the Avogadro number . It is... 

One mole of electrons carries a charge o/ L x e, where e is the charge on a single electron and L is the Avogadro constant. This quantity of charge (L X ej has a value of 96 487 C, and is known as the Faraday constant F, and so we talk in terms of faradays of charge . The basic reaction at an electrode is electron transfer to effect reduction (the analyte gains electrons) or oxidation (the analyte loses electrons), as follows ... 

Note that the Avogadro constant is al.so commonly given the symbol N/,. We will use L in this present text. 

A powder diffraction pattern establishes that silver crystallizes in a face-centred cubic unit cell. The 111 reflection is observed at 0=19.1°, using Cu-Ka radiation. Determine the unit cell length, a. If the density of silver is 10.5x10 kg m and Z=4, calculate the value of the Avogadro constant. (The atomic mass of silver is 107.9.)... 

Calculated from d = (4vspMj,/itNA)i 2 with the Avogadro constant NA b Calculated from the fitting to osmotic pressure and osmotic compressibility data (cf. Sect. 3) e Calculated from intrinsic viscosity or sedimentation coefficient data d Obtained from crystallographic data... 

Becker, P (2003), Tracing the definition of the kilogram to the Avogadro constant using a silicon single crystal. Metrologia, 40 (6), 366-75. 

The refractive index, nD, defined as the ratio of light speed at the sodium D-line in a vacuum to that in the medium, is used in obtaining the polarizability, a, of solvent molecules. The relationship between a and nD is given by a = (3Vm/ 4 rNA)( D-l)/(wD + 2), where NA is the Avogadro constant and Vm is the molar volume.4 Solvent molecules with high a-values tend to interact easily with one another or with other polarizable solute particles by dispersion forces.5 ... 

Here, Vs is the molar volume of the solvent and NA is the Avogadro constant. Some of the ionic solvation numbers obtained by this method are listed in Table 7.3. 

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