Redox reactions

• Occam's Razor

  18 Oct 08, 16:59

  Which of the reactions are redox reactions?
  
  1) CO2 + C -> 2CO
  2) 2Fe + 3Cl2 -> 2FeCl3
  3)CuCO3 -> CuO + CO2
  4) H2O + SO3 -> H2SO4
  
  Im not sure about 3) and 4), but for 1) and 2) I think they are redox. Can anyone please help me? Thanks.
  

• arigatoast

  18 Oct 08, 17:22

  1) CO2 is reduced to CO and C is oxidised to CO . so redox.

  2) Fe o.s from 0 to +3 = oxidation

     Cl o.s from 0 to -1 = reduction.

  so 2) is redox

   

  3) C  o.s +4 nv change.

   O  o.s is -2  nv change

  Cu  o.s +2 nv change

  so not redox

  4) H  o.s  +1 nv change

     O o.s  -2 nv change

    S o.s +6 nv change.

  so not redox

   

• Occam's Razor

  18 Oct 08, 17:33

  Thanks!