bonding and properties

• metallic bonding


  cations (metals) forming a lattice structure within a "sea" of delocalised electrons
• ionic bonding


  strong electrostatic attraction between cations and anions that form a lattice structure (continually repeating pattern)
• covalent bonding


  reaction between non-metals, occurs due to high electronegativity (very high core charge, rather than losing electrons, the form molecules)
• metallic - high or low MP and BP


  High melting and boiling point because electrostatic attraction between metal cations and delocalised electrons is very strong and the lattice is held very tightly together. This means a larger amount of energy is required to break bonds within the substance (within the strong intermolecular forces).
• metallic - is it a conductor


  Is a conductor of electricity as there are charged particles (delocalised electrons) that are able to move freely within the lattice that can trasfer electricity. This is in both solid and liquid state, but solids are more effective due to closer contact with other electrons.
• metallic - is it malleable or brittle


  Malleable, as when a force acts upon the lattice, and metal ions more past each other layers of the lattice still hold together due to delocalised electrons. Attractive forces between the electrons and the cations are stronger than the repulsive forces between the cations when they slide past each other.
• metallic - is it soluble


  metallic substances are generally not soluble in water because metallic bonds are non-polar and therefore not soluble in polar substances such as water. However they are soluble in non-polar substances because they are non-polar
• ionic - low or high MP and BP

  high melting and boiling point due to strong attraction between the ions so a large amount of heat energy is required to break the bonds (disrupt the lattice) and seperate the ions.
• ionic - is it a conductor


  in a solid state it is not a conductor of electricity due to the fixed position in the lattice and there are no charged particles present.

  in a molten state it is a conductor of electricity because enough heat energy has been provided to disrupt the lattice and charged ions are no longer in fixed positions, therefore electricity can be carried through the lattice.

  in a aqueous state it is also a conductor as ions have lost their fixed positions, only if it is in polar substance
• ionic - is it brittle hard or malleable


  strong electrostatic attraction between polar charges reults in the lattice being very hard rather than malleable. Is very brittle, as when a layer of the lattice is disrupted and ions are forced to slide past one another, ions of similar charge are close together. The repulsive forces of the like charges is stronger than the attractive forces and therefore the lattice is brittle.
• ionic - is it soluble


  is soluble in polar substances, such as water.
• covalent molecular - high or low MP and BP

  low melting and boiling point due to weak intermolecular bonds between molecules. Therefore only a small amount of heat energy is required to disrupt the bonds between molecules.
• covalent molecular - are they conductive


  no charge carriers within the substance, electrons are localised and atoms are neutral and they are in fixed positions.
• covalent molecular - are they hard brittle or malleable


  are very soft substances again due to the weak intermolecular bonds, when the molecules are disrupted there is very little force required to separate them from other molecules, resulting in a soft substance.
• covalent molecular - solubility


  soluble in both polar and non-polar compunds
• covalent network - high or low MP and BP


  very high melting point and boiling point because of the extremely strong covalent bonds throughout the crystal, meaning there is a lot of energy required to break the crystal/
• covalent network - is it a conductor


  is not a conductor of electricity as there are no ions or delocalised electrons within the lattice that are free to move within the crystal. Therefore charge cannot be carried
• covalent network - hard brittle or malleable


  is very hard and brittle because extremely strong covalent bonds throughout the crystal and molecules are unable to more within the structure and immobile.
• covalent network - solubility


  is not soluble in any solvent due to strong attractive forces.