Question about rusting on iron nails.

1. Mar 26, 2007

~julz~

1. The problem statement, all variables and given/known data
For my science assignment coming up i need to know more about rusting on iron nails, like how and why it occurs, what conditions help the process, what conditions don't and any other information would be very helpful.
I will be setting up my own experiment so help solve this but I would like to narrow the 'search' for conditions, why and how.

2. Relevant equations

3. The attempt at a solution

2. Mar 26, 2007

.ultimate

too easy

$$4Fe + x.H_2O + 3O_2 \to Fe_2O_3.xH_2O$$

3. Mar 26, 2007

~julz~

ok, im only in high school, and im in year 9, so could you mabye explain it so that i will understand?

4. Mar 26, 2007

.ultimate

Iron in presence of water and oxygen, from (flaky) rust on outermost layer of the metal .

conditions necessary:
1. Presence of Oxygen
2. Presence of water

Prevention
-Paiting
-Greasing
-Galvanization
-Coating with metal
-Making alloy (steel) with nickel and chromium

5. Mar 26, 2007

~julz~

So with my experiment, would the variables be....

1. Iron nails outside, dry conditions.
2. Iron nails in water, fully surrounded.
3. Iron nails outside sprayed with water.

Tell me what you think of my experiment so far.

6. Mar 26, 2007

.ultimate

1. No rusting would occur due to absense of water
2. Rusting would still occur due to absorbed $$O_2$$ in water
3. Rusting would occur due to moisture in air

Variables should be
1. Exposed to both air and water - rusting occurs
2. Exposed to water only - no rusting occurs
3. Exposed to air only

Summing it up

1. Take three test tubes A, B and C (corked)

2. Test tube A [Both air and water] - Iron nails partially immersed in water and air in test tube

3. Test tube B [Only water]- Iron nails fully immersed in boiled water (to remove dissolved air) and layer of oil aove water to prevent $$O_2$$ to dissolve in water

4.Test Tube C [Exposed to Air only] - Iron nails exposed to dry air (Use a drying agent like calcuim chloride $$CaCl_2$$

7. Mar 27, 2007

~julz~

im not sure i'll be able to get all of the requirements, but i will try to manage with what i have got. Thank you for all your help .ultimate