bonding

• what is ionic bonding

  electrostatic force between oppositly charged ions.
• what is a covalent bond

  shared pair of electrons.
• what is a dative/ co-ordinate covalent bond

  where the shared pair of electrons in a covalent bond come from one species
• what is metallic bonding

  electrostatic force of attraction between positive metal ions and delocalised electrons
• what factors effect the strength of metallic bonding

  number of protons/ nuclear charge= stronger MB. number of delocalised electrons(electrons in outer shell)= stronger MB. size of ion = stronger MB in smaller ions
• what is the structure of ionic compounds

  giant ionic lattice
• what is the two structures of covalent compounds

  simple covalent and macromolecular
• what is the structure of a metallic compound

  giant metallic lattice
• properties of ionic compounds.

  high M+BP, atrong electrostatic force of attraction. soulable in water. does not conduct when solid as ions are not free to move, conduct when molten
• properties of simple covalent molecules.

  low M+BP, weak intermolecular forces (VDW). poor soluability in water. cant conduct as electrons are not free to move.
• properties of macromolecular

  high M+BP, strong covalent bonds. insoluable. diamond does not conduct as it has no delocalised electrons, graphite conducts as it has delocalised electrons.
• properties of metallic compounds

  high M+BP, strong electrostatic force of attraction. insoluable, conducts due to delocalised electrons. malleable as structure is layers which can slide over eachother, ductile and sonorous
• what are the different shapes of molecules and their angles

  linear- 180. trigonal planar- 120. tetrahedral- 109.5. trigonal pyramidal-107. v-shape-104.5. trigonal bipyramidal- 2x90, 3x120. octahedral- 90.
• what is the expalnation for the shape of a moleule

  if there are lone pairs, it will puch electrons down due to repulsion to get as far away as possible. if there are no lone pairs, electrons are equally repelled.
• what is electronegativity

  ability of an atom to attract a pair of electrons towards itself in a covalent bond.
• what are the most electronegative elements

  flourine, oxygen and nitrogen
• what is the trend of electronegativity

  increase across a period as atomic radius decreases and nuclear charge increases. decreases down a group as atomic radius increases and sheilding increases therefore nuclear charge decreases
• what are the types of intermolecular forces, from strongest to weakest.

  hydrogen bonding, dipole-dipole and van der waals
• what are the factors affecting VDW

  larger the molecule the stronger the VDW forces. stronger in straight chains
• when do dipole - dipole forces occur

  due to an uneven distribution of electrons, occur with electronegative elements
• when does hydrogen bonding occur

  when hydrogen is attached to fluorine, oxygen or nitrogen only, due to a large difference in electronegativity.
• how do you find the shape of any molecule? e.g. ClF3

  the group of the central atom, the number of atoms covalently bonded and the charge of the molecule(+1 -> -1 and -1-> +1). add values together and divide by 2. Cl is group 7, 3 atoms bonded and no over all charge 7+3+0=10/2=5, 3 bonded, 2 lone= trigonal bipyramidal.