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Topic 1bii - Structure and Bonding - Coggle Diagram
Topic 1bii - Structure and Bonding
Ionic compounds
Strong electrostatic forces
of attraction between
oppositely
charged ions
Form a
lattice
, in a regular arrangement
Melting and boiling points
High
melting and boiling points
They are
solid
at room temperature
There are many strong ionic compounds
Large amounts of energy
are needed to break the bonds
Between
metals and non-metals
Conduction of electricity
Conduct when molten or dissolved in water
Cannot conduct when solid as the ions cannot move
Hard, reflective solids
Usually soluble
in aqueous solutions
Brittle
- If force is applied, the positive ions could move next to other positive ions, the repulsion between the charges breaks up the lattice structure
Simple covalent compounds
Formed when a pair of electrons are shared between two atoms
Strong
Form between
non-metals
Melting and boiling points
Low
Often liquids and gases at room temperature
The
weak
intermolecular forces are overcome, the covalent bons aren't broken
Very little energy needed
Conduction of electricity
Cannot conduct
No overall charge ot charged particles that can seperarte
Powdery and easy to crumble
Irregular
structure
Simple molecular substances
Consists of just a few atoms joined to each other by a
strong
covalent bond
Usually have
low melting and boiling points
Usually a
gas or liquid
at room temperature, weak intermolecular forces
Do not conduct electricity
as molecules aren't electrically charged and don't contain electrons that are free to move
Can conduct in
solution
, when in water, they can dissolve, forming ions which can move around
Usually
insoluble
in water
Intermolecular forces increase with size
Giant covalent structures
Consists of many atoms
Joined by
strong
covalent bonds
Arranged in a regular
lattice
High
melting and boiling points
Diamond
Made from
carbon
Each atom is bonded to
four
others
No free electrons
, doesn't conduct electricity
Diamond is very
hard
, atoms held together by strong covalent bonds
Used in cutting tools
Atoms for a tetrahedral layered structure
Graphite
Made from carbon (
allotropes
with diamond, different forms of the same element in the same state)
weak
intermolecular forces between the layers
Layers can
slide
over each other
Each carbon atoms has
1 un bonded electron
which is free to move, so Graphite
can conduct
electricity
Used for
electrodes
in batteries and for electrolysis
Graphite is also
slippery
and can be used as a lubricant
Atoms form a regular
hexagonal
structure
Insoluble
in water
Metals
Left
hand side of the periodic table
Malleable
- they can be pressed into shape without shattering
Consist of a giant
lattice
of positively charged metal ions
sea
of delocalised electrons, which can move
Metal bonds are
strong electrostatic
forces of attraction between
positive metal
ions and
delocalised electrons
Ductile
- can be pulled into wires without breaking
Insoluble
in water
Shiny
High
melting and boiling points
Good
conductors
High density
Other large molecules
Graphene
Single layer
of graphite
Each carbon atom is bonded to
three
other atoms
Regular
lattice
structure
Non bonding delocalised electrons can move through the structure, so it
conducts electricity
Very strong and
flexible
Almost
transparent
Fullerenes
Bucky balls
C60
Carbon atoms arranged in pentagons and hexagons
Conducts electricity
Weak
intermolecular forces
Nano tubes
Conduct electricity
very
strong
Polymers
Made from monomers joined together
Hydrocarbons
Limitations of models
Written formula
Empirical formula
- Doesn't show how atoms are arranged or the number of atoms
Molecular formula
- Doesn't show how atoms are arranged
Structural
- Doesn't give and idea about how the atoms are arranged
Drawn structures
- Doesn't show 3D shape or bonding of electrons, doesn't show to outer electrons
Ball and stick models
- Doesn't showing bonding of electrons or thew chemical symbol, only show small part of molecule
Dot and cross diagrams - Doesn't show the 3D shape of the molecule
Space filling diagrams - Dones't show 3D shape or the whole molecule