Presentation on theme: "Section 7.3 – Using Chemical Formulas"— Presentation transcript:
1 Section 7.3 – Using Chemical Formulas They allow chemists to calculate a number of characteristic values for a given compound.
2 Formula MassLike individual atoms, the formula mass of any molecule, formula unit, or ion is the sum of the average atomic masses of all the atoms represented in its formula. Reported in amu (atomic mass units).
3 Example – Water (H2O) 1 H atom = 1.0079 amu 1 O atom = 15.9994 amu 1 water molecule =(2 x ) + (1 x )= amu/molecule