chemistry f3

• 6 metal properties

  1. conduct electricity
  2. conduct heat
  3. shiny when cut
  4. Malleable
  5. ductile
  6. sonorous
• definition of isotopes: atoms with the same number of protons but different number of neutrons
• Semi metals / metalloids

  1. Silicon
  2. boron
  3. germanium
• protons have a positive charge - electrons have a negative charge - neutrons have a neutral charge
• period number: occupied electron shells

  group number: number of outermost shell electrons
• Group I metals: alkali metals
• Li lithium 3

  Na sodium 11

  K potassium 19

  Rb rubidium 37

  Cs caesium 55

  Fr francium 87
• Group 1 elements MP and BP decrease down the group
• metals that tarnish rapidly in air are stored in paraffin oil
• Group 1

  react with oxygen to form oxides

  react with chlorine to form chlorides

  react with water to form hydroxide and hydrogen
• Reactivity of group I metals increase down the group
• Group II elements: alkaline earth metals
• reactivity of group II elements increase down the group
• group II react with halogens to form halides
• Be Beryllium 4

  Mg Magnesium 12

  Ca Calcium 20

  Sr Strontium 38

  Ba Barium 56

  Ra Radium 88
• Group VII elements: halogens
• 9 Fluorine is a pale yellow gas

  17 chlorine is a greenish yellow gas

  35 bromine is a reddish brown liquid

  53 iodine is a shiny black solid
• Group VII elements MP and BP increase down the group
• Reactivity of group VII elements decrease down the group
• Group 0 elements: noble gases
• group 0 elements MP and BP increase down the group
• noble gases are not reactive - chemically inert
• fully occupied outermost electron shell

  octet structure

  duplet structure
• electrolytes:

  conduct electricity in molten (melted) state and in aqueous solution (water dissolved) but not in solid state
• electrostatic forces of attraction between negative and positive atoms - ionic bond
• lattice don’t stay in pairs and are packed together in regular arrangement
• Strong electrostatic forces of attraction between metal cations and delocalised electrons are called


  metallic bond
• Ionic bonding


  oppositely charged ions have strong electrostatic force of attraction
• lattice 


  Packed together in regular arrangement

  no directional (attracted to opposite charge)
• Metallic bond


  strong electrostatic force of attraction between metal cation and sea of delocalised electrons