Separate Chemistry 1

• Haber process

  nitrogen + hydrogen <---> ammonia

  N + 3H = 2NH
• transition metals sit in the middle of the table
• transition metals

  hard, strong, shiny, malleable, conduct heat + electricity, high mp, high density
• compounds of transition metals are colourful
• pure metals are malleable because they have a regular arrangement of the same atoms. the layers can slide

  alloys are composed of different sized atoms which are not regularly arranged. This means they cant slide and are much stronger.
• bronze + copper = tin

  carbon + iron = steel
• metals corrode in the presence of oxygen and water to form metal oxides

  usually caused by redox reactions (metal loses oxygen gains)
• ways to prevent rusting

  painting

  coating with a barrier

  oiling or greasing
• titrations are used to find out how much acid is needed to neutralise an alkali (or vice versa)
• titration

  using a pipette measure a set vol of alkali, put into a flask

  add indicator drops (methyl orange or phenolphthalein)

  fill a burette with a standard solution of acid

  use the burette to add the acid to alkali a bit at a time

  swirl regularly

  indicator changes colour when all alkali is neutralised

  record volume of acid used to neutralise alkali

  repeat
• methyl orange

  yellow in alkali, red in acid

  phenolphthalein

  pink in alkali, colourless in acid