Help! Mandatory Pracs (1 Viewer)

[Karla Renae]

Have been given this assignment. Straight from dot points
Preform a first hand investigation to compaire and describe the rate of corrosion of materials in different
-oxygen concentrations
-temperatures
-salt concentrations

Has anyone done this experiment in class. If so got any hints i'm fairly stuck and it's an assessment task

 

[tennille]

For the oxygen concentration one, boil the water. So you should have one with boiled water (which is stoppered to prevent air going through) for low O2 concentrations (you should also add a layer of oil onto it to prevent O2 getting in), and one with normal distilled water which isn't stoppered for the higher O2 concentration. You should also have one only half covered in distilled water.

For the temperature one, place three iron nails in a test tube, stopper the test tube and place one in an oven (set above room temp, but not too high), one at room temp, and one in a fridge.

For different salt conc. place 4 iron nails in a test tube. Completely cover one nail with distilled water (control), and cover the rest of the nails in different concentrations of salt solutions.

For rach of the experiments, remove some solution from each test tube and test for Fe2+ ions with universal indicator and potassium hexacyanoferrate (III) solution (turns from yellow to blue in the presence of Fe2+ ions).