Molecular weight

Molecular weight (molecular weight) - the relative weight of a molecule of a substance expressed in international units atomic mass, which is adopted by 1/12 of the mass of an atom of the isotope carbon - 12. Gram-molecule or moth called mass of a given substance in grams, numerically equal to its molecular weight.
Cm. also Atomic weight.

Molecular weight (or relative molecular mass - weight molecules simple or complex substances, expressed in international units of atomic masses.
As an international unit of atomic masses adopted 1/12 mass of carbon isotope with mass number 12.
Molecular weight equal to the sum of the atomic weights of atoms forming part of a molecule of the substance; therefore, knowing the chemical formula of a substance can be calculated his Feet century, for Example, the molecular weight of ethyl alcohol WITH2N5IT is: 2·12,011 + 6·1,008 +1·15,999=46,069. If chemical formula unknown, M. C. determine experimentally, using numerous methods that are described in separate manuals.
The number of this (simple or complex) substances in grams, numerically equal to his Feet century, called gram-molecule, or mol. For example, 1 mol O2 = 2·15,999 = 31,998 g, 1 mol CO2 is 1·12,011 + 2·15,999=44,009 g etc.