# Chemistry

posted by .

the corrosion of iron is similar to the reactions that occur in an electrochemical cell. Oxidation and reduction occur at separate places on the metal and the circuit is completed by an electrolyte in solution one possible corrosion is Fe(s)+O2(g) + H2O(l) --> Fe^2+(aq) + OH-(aq)
a. identify the substances oxidized and the substance reduced?

b. using the half reactions write the balanced redox equation

c. prove the reaction is spontaneous at standard conditions

• Chemistry -

The substance oxidized is the one that loses electrons. The substance reduced is the one that gains electrons. It looks like Fe changes from zero to +2 and oxygen changes from zero to -2.

Fe ==> Fe^2+ + 2e
O2 +4e + 2H2O ==> 4OH^-
Multiply #1 by 2 and #2 by 1 and add them for the complete redox reaction.

Look up Eo values (be careful with the signs) and add the oxidation half to the reduction half. Add the E values for each and it should come out a positive number.

• Chemistry -

Eo cell- Eo 1 + Eo 2 = -0.44+ +1.23= 0.79V?
how do i explain that its spontaneous because delta H is greater then O

• Chemistry -

The reaction is spontaneous because Ecell is +. I looked up the Eo values. E for Fe==> Fe^2+ is 0.44
O2==> OH^- is +0.401 Ecell = 0.841 which is about the same as you obtained but with different numbers.

## Similar Questions

1. ### college chemistry - answer check ASAP!

The corrosion of iron can be thought of as an electrochemical cell reaction. Calculate the voltage difference between two points of corroding iron differing only in their partial pressures of oxygen: 0.20 atm of oxygen at one point …
2. ### chemistry

1. How do you know if metals are most susceptible to corrosion?
3. ### chemistry

How does (a) copper and (b) zinc affect the corrosion rate of iron?
4. ### Chemistry

The reaction below shows the corrosion process of iron. Calculate E°cell for the corrosion process and state whether you would predict that this is a spontaneous or nonspontaneous process. 2 Fe (s) + O2 (g) + 4 H+ (aq) → 2 Fe2+ …
5. ### chemistry- electrochemical cell

What makes this an oxidation-reaction? 3Ag2S+2Al(s) -> Al2S3+6 Ag(s)?
6. ### chemistry

"Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of the following aqueous solution: CuBr2(aq)" Possible oxidation reactions: 1. 2Br- -> Br2 + 2e- = -1.09 2. 2H2O -> O2 + 4H+ + 4e- …
7. ### chemistry

Describe the following types of corrosion and give a practical example of each 1.pure chemical corrosion 2.pure electrochemical corrosion
8. ### Chemistry

3. The diagram shows an electrochemical cell with a gold strip (left) and aluminum glasses (right). In your response, do the following: • Label the cathode and the anode, including the charge on each. • Show the flow of electrons. …
9. ### Chemistry

What assures that there is no charge build up in a voltaic cell as oxidation and reduction occur?
10. ### AP Chemistry

Sodium can be extracted by heating naturally occurring salt until it is molten. An electrochemical process is then used to extract the sodium. Cl2 is produced at the anode, and Na is collected at the cathode. 1. Write the half-reactions …

More Similar Questions