Corrosion - Science

Corrosion I

Aim: To investigate the factors that cause rusting in iron. 

Equipment:

• Test tubes
• Test tube rack
• A bung
• four iron nails
• Boiled water
• Tap water
• Salty water
• Cooking oil
• Calcium Chloride

Method:

1. Label four test tubes A - D and place them in a test tube rack.
2. Test tube contents:

• A = Iron nail.
• B = Iron nail and tap water.
• C = Iron nail and salty water
• D = Iron nail, boiled water and oil. 

      3. Leave the test tubes undisturbed for at least three days.

Hypothesis: Test tubes A to D can be expected to rust more and have the most visual changes, rather than test tubes E to H. 

Observations: Complete the table.

Test Tube	Conditions present or absent	Observations
A	Air	Test tube A had shown some slight rusting on the iron nail.
B	Water and air	Test tube B had corroded the most out of all the test tubes and has shown some turned the water orange.
C	Salt, water and oil	Test tube C has shown some corroding and has turned the water slightly orange.
D	Boiled water, and oil	Test tube D has shown some corroding and has turned the water slightly orange.

Corrosion II

Aim: To investigate a number of techniques that may prevent rusting. 

Equipment: 

• Four test tubes
• Test tube rack
• A bung
• Four iron nails
• Tap water
• Vaseline gel
• Nail polish or paint
• Zinc pellets or magnesium ribbon

Method:

1. Label four test tubes A - D and place in a test tube rack.
2. Fill all test tubes with equal volumes of water - enough to cover the nails.
3. Test tube contents:

• A = Iron nail, calcium chloride and a bung. 
• B = Iron nail covered in Vaseline and water. 
• C = Iron nail painted with nail polish or paint.
• D = Iron nail with a small piece of magnesium ribbon wrapped around it, or with zinc pellets added to the test tube.

      4. Leave the test tubes undisturbed for at least three days. 

Observations: 

Test Tube	Conditions present or absent	Observations
E	Calcium Chloride	Test tube E had shown no signs of corrosion and has stayed the same from the beginning.
F	Water and vaseline	Test tube F has slightly corroded at the bottom of the iron nail.
G	Water and nail polish/paint	Test tube G has shown some corroding and has turned the water orange.
H	Zinc/Magnesium	Test tube H has shown corrosion and corroded the zinc pellet.