topic c1- atomic structure + the periodic table

• atoms contain

  • electrons
  • neutrons
  • protons
• electron relative mass

  very small
• electron relative charge

  -1
• neutron relative mass

  1
• neutron relative charge 


  0
• proton relative mass

  1
• proton relative charge 


  +1
• mass number

  the top number on an element
• atomic number

  the bottom number on an element
• atomic number

  number of protons
• number of protons

  number of electrons
• atoms are neutral

  so charges cancel out
• mass number

  sum of the number of protons and neutrons
• isotope

  • a change in the number of neutrons
  • protons stay the same
• ions

  • a change in the number of electrons
  • protons stay the same
• compound

  two or more substances chemically bonded together
• mixture

  • two or more substances mixed together
  • not chemically bonded
• separating methods

  • evaporation/ crystallisation
  • filtration
  • chromatography
  • distillation
• evaporation and crystallisation

  
• evaporation and crystallisation

  • heat a solution, some solvent evaporates
  • once crystals form, remove the heat
  • dry the crystals out
• filtration

  
• filtration

  removes insoluble solids from a liquid
• chromatography

  
• chromatography 


  separates compounds from a mixture
• simple distillation

  
• simple distillation

  separates mixtures
• fractional distillation

  
• fractional distillation

  separates multiple mixtures
• history of the atom

  • plum pudding model
  • rutherford's alpha scattering experiment
  • nuclear model
• plum pudding model

  
• plum pudding model

  • solid spheres of positive charge
  • with small negative charges floating within
  • later to be named electrons
• nuclear model

  
• nuclear model

  • positive nucleus in the centre
  • electrons orbit
  • 2, 8, 8 electron structure
  • lots of empty space
• group 1 elements

  alkali metals
• alkali metals- examples

  • lithium
  • sodium
  • potassium
• alkali metals- properties

  • very reactive
  • 1 electron in outer shell
  • form ionic compounds
  • soft to touch
• group 7 elements

  halogens
• halogens- examples

  • fluorine
  • chlorine
  • bromine
• halogens- properties

  • very reactive
  • 7 electrons in outer shell
  • coloured vapour non metals
• group 8 elements (0)

  noble gases