sommer: examples and translations in context. 1  Par consÃ©quent, si nous voulons vraiment la dÃ©mocratie et l'Ã©galitÃ© devant la loi, nous devons sommer l'armÃ©e turque de se retirer de Chypre, tout comme nous exigeons de l'armÃ©e syrienne qu'elle quitte le Liban.
This number, Avogadro's number, is 6.022x10 23. The mass in grams of one mole of a compound is equal to the molecular weight of the compound in atomic mass units. One mole of a compound contains 6.022x10 23 molecules of the compound.The mass of 1 mole of a compound is called its molar weight or molar mass.The units for molar weight or molar mass are grams per mole. Here is the formula for determining the number of moles of a sample:ne mole of a compound contains 6.022x10 23 molecules of the compound. The mass of 1 mole of a compound is called its molar weight or molar mass. The units for molar weight or molar mass are grams per mole. Here is the formula for determining the number of moles of a sample:
Multiply the atomic weight of each element by the number of atoms of the element in the molecule, and add these to calculate the compound molar mass. In the example, the molar mass of Na2SO4 is (23 x 2) + (32 x 1) + (16 x 4) = 142 grams per mole.Divide the known mass of the compound by its molar mass to calculate the number of moles. For example, suppose the mass of your sample of Na2SO4 is 20 g. The number of moles equals 20 grams /142 grams/mole = 0.141 moles.Multiply the number of moles by the Avogadro constant, 6.022 x 10^23, to calculate the number of molecules in your sample.In the example, the number of molecules of Na2SO4 is 0.141 x 6.022 x 10^23, or 8.491 x 10^22 molecules of Na2SO4.n the example, the molar mass of Na2SO4 is (23 x 2) + (32 x 1) + (16 x 4) = 142 grams per mole. Divide the known mass of the compound by its molar mass to calculate the number of moles. For example, suppose the mass of your sample of Na2SO4 is 20 g. The number of moles equals 20 grams /142 grams/mole = 0.141 moles.