atoms
only noble gas elements exist this way in nature
ionic bonds
transfer of electrons
metallic bonds
sea of electrons within a metal
covalent bonds
share electrons
characteristics of covalent bonds
formed by two non-metals, generally low melting/boiling point, can be solid liquid gas,
compounds for covalent bonds are called....
molecules
what is the chemical formula called
molecular formula
lewis structure
model to show how atoms are arranged and bonded
diatomic molecules
special kind of molecular compound in which two of the same atom are joined by a covalent bond
molecular formula
the chemical formula of a molecular compound
octet rule for covalent bonding
electron sharing tends to occur so that atoms, with shared electrons included, attain a full outer shell
exceptions to the octet rule
hydrogen and helium want 2 electrons, beryllium is okay with 4, and boron is ok with 6
shared pair of electrons
bonding pair between two atoms, represented by a line
inshared pair of electrons
pair of valence electrons not shared, represented by two dots
single covalent bond
two atoms held together by the sharing of one pair of electrons
doube covalent bond
two atoms share two pairs of electrons
triple covalent bond
two atoms share 3 pairs of electrons
bond dissociation energy
total energy required to break the bond between two covalently bonded atoms
shorter the bond length _______ the bond
stronger
large energy=
strong bond
carbon can bond to other carbon atoms to form
long chains, branched chains, and ring structure
polyatomic ions
tightly bound group of atoms that have a positive or negative charge and behave as a unit
resonance structure
when it is possible to have 2 or more valid electron dot structures
excpetions to the octet rule
some atoms will eccept more than 8 outer electrons, phosphorus excepts 10 and sulfur excepts 12