Copper Rusting

Science Project: Copper Rusting

Supplies Needed: 2 new pennies, orange juice, coke, 2 glass cups, fridge (not pictured).

Procedure for Copper Rusting

Day 1: Tuesday, April 13

Result: Both pennies are brand new.

Day 2: Saturday, April 17

Result: The penny in the Coca Cola is slighty more rusted than the penny in the orange juice.

Day 3: Wednesday, April 21

Result: Both pennies are slighty more rusted than they were 4 days ago, but the penny in the Coca Cola is still more rusted than the penny in the orange juice.

Day 4: Sunday, April 25

Result: The penny in the Coca Cola is almost completely rusted, whereas the penny in the orange juice has rust, but not nearly as much as the penny in the Coca Cola.

Information: The pH level affects the acidity of a product. Orange juice contains citric acid and has a ph of 3.5. Coca Cola has phosphoric acid added to it, which is an approved food grade acid. The ph level of Coca Cola is 2.6 which is a higher acidity than that of orange juice. Before doing the project, I thought the orange juice would have a higher acidity than the Coca Cola, but the ph levels probably would have determined that the Coca Cola would rust at a faster rate than the orange juice due to its higher ph level.

By looking at this scale, it looks as if the ph of orange juice and the ph of coca cola is the same, but when you get technical, the ph of coca cola is actually higher.