T he Mole and Avogadro’s Number. Mole ( n ): the amount of substance 6.02x10 23 particles (atoms or molecules) of a substance The same number of particles as atoms in 12 grams of carbon-12. Review. How many atoms are there in 1.2 moles of oxygen?
2. A sample of zinc chloride contains 3.1x1019 molecules.
a. How many moles is this?
b. How many zinc ions?
c. How many chloride ions?
Atomic mass (A): the mass of an atom of an element relative to (compared to) other elements (g/mol)
Formula mass: sum of the atomic masses of the atoms in the compound’s formula (IONIC) (g/mol)