Mind map of types of substances and their properties, particles, forces and structures for the NCEA level 2 Chemistry external Bonding, structure, properties and energy changes (Chem 2.4).
Strong electrostatic forces of
attraction between the
electrons and positive nuclei
of metal atoms
Properties
Conducts
electricity
They have free electrons that
are able to move and hence
conduct a charge
Insoluble
in water
The electrostatic
forces between the
particles are too
strong to be
overcome by the
attractive forces
between water and
the metal
Malleable and
Ductile
The non-directional
attraction of the valence
electrons means that metal
atoms can slide past each
other without breaking the
overall structure
High melting
and boiling
point
There are strong
electrostatic forces
which require lots of
energy to overcome
Structure
Free electrons from
outer shell of metal
atoms alternate with
positive metal ions
Particles
Positive
nuclei and delocalised
electrons
Covalent Network
Properties
Do not
conduct
electroicty
They have no free
electrons or ions
Usually
Insoluble
in water
Many molecular substances are not
polar, since water is polar and like
dissolves like, only polar substances
will dissolve in water. Polarity is
decided by the shape of the molecule
(see structure)
Low melting and
boiling point
The weak
intermolecular
forces do not
require a lot of
energy to overcome
Forces
Between
Particles
Weak intermolecular forces of
attraction between the molecules
Particles
Molecules made up of atoms
(strong intramolecular covalent
bonds between these atoms)
Structure
2 Regions of
negative
charge
Linear
4 regions
of negative
charge
Two bonded,
two non-bonded
Bent 4:
All bonded
Tetrahedral
Three bonded,
one non-bonded
Trigonal Planer
3 regions of
negative charge
All bonded
Trigonal Planar
Two bonded, one
non-bonded
Bent 3
Molecular
Particles
Atoms
Structure
2D
2D hexagonal layers. Within each
layer the atom is bonded to three
others, with delocalised electrons
between the layers
3D
3D lattice where each atom is bonded
to 4 others by strong covalent bonds.
Forces Between
Particles
Strong covalent bonds
between atoms
Properties
Graphite is soft
Layers are held together by
weak bonds so can slide
past each other
Diamond is
hard
Strong covalent bonds makes the
structure very rigid
High melting
and boiling
point
Strong covalent bonds so require
lots of energy to overcome.
Diamond does not
conduct, but
graphite does.
Diamond does not have free
electrons so does not conduct
whereas graphite does
Ionic
Forces Between
Particles
Strong electrostatic forces of
attraction between oppositely
charged ions
Structure
Regular 3D lattice structure
consisting of alternating
cations and anions
Particles
Negatively charged
anions and
positively charged
cations
Properties
Conduct when
molten or in
solution
Electrons are removed from the
rigid structure so can move and
carry a charge
High melting
and boiling
points
Strong electrostatic forces of
attraction so require large
amounts of energy to
overcome
Dissolve in
polar solvents
The cations are attracted to
the negative dipole whilst the
anions are attracted to the
positive dipole
Do not conduct in
solid form
Electrons are fixed in the 3D
lattice so cannot move or carry a
charge