CHAPTER 2. ATOMS, MOLECULES AND IONS. Contents. The Atomic Theory of Matter The Discovery of Atomic Structure The Modern View of Atomic Structure Atomic weights The Periodic Table Chemical Substances: Formulae and Names Ions and Ionic Compounds Naming Inorganic Compounds
ATOMS, MOLECULES AND IONS
E.g. There are three binary compounds that form between barium and nitrogen. There was 4.9021 g , 9.8050 g and 14.7060 g of Ba per 1.0000 g N in the three compounds. Show that these compounds obey the law of multiple proportions.
Atomic mass scale:
Average Atomic Masses
where f1 = the fractional abundance of isotope 1 and AM = the atomic mass.
E.g. Determine the atomic mass of boron if the masses of the two isotopes are 10.013 amu and 11.009 amu and the fractional abundances are 0.1978 and 0.8022, respectively.
E.g. 2 Using the periodic table, determine the fractional abundance of the 35Cl and 37Cl isotopes if their masses are 34.969 and 36.966, respectively.
IUPAC and Common Usage Methods of naming used for both organic and inorganic compounds.
Organic compounds = predominantly carbon containing compounds.
Inorganic compounds = all others
Binary ionic compounds: compounds having a cation (a metal) and an anion (one of the main group anions).
Binary molecular compounds:
E.g. the combustion of methanol produces water and carbon dioxide:
CH3OH(l) + O2(g) CO2(g) + H2O(l)