1.7 oxidation, reduction , redox

• oxidation is the process of electron loss, it involves an increase in oxidation number
• reduction is the process of electron, it involves a decrease in the oxidation number
• the oxidation numbers of the elements in a compound add up to zero
• what are reducing agents?


  lose electrons
• what are oxidising agents?


  gain electrons
• what is the oxidation state of uncombined elements?


  0
• what is the oxidation state of an ion?


  the same as the ion charge
• what is the oxidation state of group 1 elements


  +1
• what is the oxidation state of group 2 elements?


  +2
• what is the oxidation state of aluminium?


  +3
• what is the oxidation state of hydrogen?


  its always +1 except in hydrides (bonded to metal) when its -1
• whats the oxidation state of flourine?


  -1 (most electronegative)
• what is the oxidation state of chlorine?


  -1 except when bonded with flourine or oxygen which is more electronegative so becomes +1
• whats the oxidation state of oxygen?

  -2

  except in peroxides is -1

  +2 when bonded with flourine