March 28, 2024, 07:08:22 PM
Forum Rules: Read This Before Posting


Topic: Oxidation of Iron  (Read 2692 times)

0 Members and 1 Guest are viewing this topic.

Offline aaron-ch

  • Very New Member
  • *
  • Posts: 1
  • Mole Snacks: +0/-0
Oxidation of Iron
« on: August 08, 2012, 04:28:53 PM »
Hi We were given the problem:

"Write the chemical equation for the oxidation of Fe and of Al.  Use ΔGf° to determine whether either process is spontaneous at 25°C"

I am really confused with how I would write the oxidation equations with out being given information about how Fe and Al ionize, and what they react with?

please help...   


Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: Oxidation of Iron
« Reply #1 on: August 09, 2012, 01:24:56 AM »
Hi We were given the problem:

"Write the chemical equation for the oxidation of Fe and of Al.  Use ΔGf° to determine whether either process is spontaneous at 25°C"

I am really confused with how I would write the oxidation equations with out being given information about how Fe and Al ionize, and what they react with?

please help...   



The key word here is oxidation!
So Fe and Al are reacting with oxygen.
So now you can write the balanced equations.
Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Offline mugabo daniel

  • Regular Member
  • ***
  • Posts: 12
  • Mole Snacks: +0/-3
Re: Oxidation of Iron
« Reply #2 on: August 09, 2012, 04:06:48 PM »
iron undergoes oxidation to form two compounds i.e. iron(ii) oxide and iron(iii) oxide depending on oxygen content.
    2Fe + O2 --> 2FeO
    4Fe + 3O2 --> 2Fe2O3
Try to find energy changes for the above reactions and substitute in the Gibbs formula;
      DG = DH-TDS
  where H = enthalpy change
           T = temperature in kelvin
           S = entropy change
Aluminium undergoes oxidation to form aluminium oxide
   2Al + 3O2--> Al2O3
if G is negative then the reaction is spontaneous and viceversa.
this is what i know u can correct me if am wrong.

Sponsored Links