6.1 shapes of molecules and ions Flashcards
Define
Bonding and lone pairs
A pair of electrons in a
covalent bond are called a
bonding pair.
Pairs of
electrons that are not
involved in bonding are
called lone pairs.
what determines the basic shape of the molecule.
Electron pairs are clouds of negative charge, so there is mutual repulsion between them, forcing them as far apart as possible.
This means the number of electron pairs around the central
atom(s)
electron pair types in order of repulsion
most -> least
lone-pair + lone pair
lone-pair + bonded pair
bondend pair+ bonded pir
Bond length
is the distance
between the nuclei of two
bonded atoms.
Bond angle
is the angle
between two covalent bonds.
bond angle of
tetrahedral
109.5
bond angle of
pyramidal
107
bond angle of
non linear
104.5
bond angle of
trigonl planar
120