Ch 22
Section 1
Stability in Bonding
Compound
  The combination of two elements to form a new
substance.
  When elements combine to make compounds the
new substance usually has different characteristics
than the elements.
  Have different physical and chemical properties.
Formulas
  Chemical formula- tells what elements a
compound contains and the exact number
of atoms of each element in a unit of that
compound.
  Subscript-means written below
  Subscript tells how many atoms are in the
compound.
Formulas
  Silicon dioxide has 1
silicon atom and 2 oxygen
atoms.
Atomic stability
  Atoms want to be
stable.
  To be stable an atom
likes to have 8 electrons
flying around it. (except
hydrogen and helium)
  Noble gasses have 8
electrons naturally so
they don’t make
compounds normally.
Outer levels
  Two elements that don’t have the 8 electrons that
they want can combine to form a chemical
compound which gives both elements the stability
they desire.
Ions
  Atoms that have lost or gained electrons.
  Cation-positively charged ion
  Anion- negatively charged ion