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Chemical Bonding - Coggle Diagram
Chemical Bonding
Covalent Bond
Simple molecular Structure
- strong covalent bonds between atoms
- weak intermolecular forces between molecules
intermolecular forces
Van der Waals' forces
- temporary dipole --> present in all molecules
- permanent dipole --> present in polar molecules
Hydrogen Bond
- molecules with F-H, O-H AND N-H
- stronger than Van der Waals' forces
low melting and boiling points
- small amt of energy needed
poor electrical conductivity
- do not contain mobile ions or delocalised electrons to act as charge carriers to conduct electricity
- exceptions: strong acids, polar molecules, graphite
insoluble in water
- except for polar molecules
- ability of molecules to form hydrogen bonds with each other
Giant Covalent Bond
- strong covalent bond between atoms
high melting and boiling points
- large amt of energy needed to overcome strong covalent bonds between atoms
Diamond
- bonded tetrahedrally to 4 other carbon atoms
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does not conduct electricity
- all outer shell electrons are used
- no delocalised electrons
Graphite
- made up of hexagonal layers
- within each layer, each C forms strong covalent bonds w 3 other C --> hexagonal ring
soft and slippery
- layer of C are held loosely by weak intermolecular forces of attraction
- C slides over each other when force applied
able to conduct electricity
- one valence e per C not used
- delocalised electrons along the same plane can conduct electricity
Metallic Bond
Giant metallic lattice structure
- strong electrostatic forces of attraction between delocalised electrons and the metal cation
- non-directional bonding pattern
Pure Metals
high melting points
- giant metallic lattice structure
- large amounts of energy is required to overcome bond
good electrical conductors
- presence of positive ions surrounded by delocalised electrons
- delocalised electrons act as charge carriers to conduct electricity under the influence of a potential difference
- conductivity increases from Na to Al (Al has the greatest number of delocalized electrons)
malleable and ductile
- electrons do not belong to a particular metal atom
- layer of positive ions slides over the other without disrupting the metallic bond
Alloys
strong metals
- atoms are of different sizes --> break up the regular arrangement of the atoms in pure metals
- layer of atoms in alloys cannot slide over each other easily when force is applied
lower melting point then pure metal
- melt over a range of temperatures
good electrical conductor
- prescence of delocalised ions
uses of alloys
- make metals stronger and harder
- lower melting points
- more resistant to corrosion
Ionic bond
giant ionic lattice structure
strong electrostatic forces of attraction between cations and anions
non-directional bonding
good electrical conductivity
- only in molten or aqueous states
- (bonding) is overcome
- ions are free to move around
- electricity can be conducted by mobile ions
Hard but Brittle
- ions with similar charge from neighbouring layers face each other
repulsive force between similar charges spilts crystals
soluble in water, insoluble in organic solvent
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