On the next pages there are examples of some irreversible changes Investigating RUSTING My hypothesis: I think that the following conditions are needed for nails to rust: In order to test my hypothesis I did the following experiment I took test tubes and placed nails in each tube …….. …… The conditions in each tube were different as below A B C D E The nails were left in the test tubes for days …………… Results of rusting experiment: Contents Conditions Result Tube A Air and water Air water Tube B Air + Air, Drying agent no Tube C Boiled water Water, no oxygen Tube D Air and Air sea water Water salt Nothing Normal Tube E (control) A drying agent is a chemical that takes water from the air and keeps the air dry Conclusion: In order to rust a piece of iron needs the following conditions: Metal can be painted Chain should be coated with oil
On the next pages there are examples of some irreversible changes Investigating RUSTING My hypothesis: I think that the following conditions are needed for nails to rust: In order to test my hypothesis I did the following experiment I took …….. test tubes and placed …… nails in each tube The conditions in each tube were different as below A B C D E The nails were left in the test tubes for …………… days Results of rusting experiment: Contents Conditions Result Tube A Air and water Air water Tube B Air + Drying agent Air, no Tube C Boiled water Water, no oxygen Tube D Air and sea water Air Water salt Tube E Nothing (control) Normal A drying agent is a chemical that takes water from the air and keeps the air dry Conclusion: In order to rust a piece of iron needs the following conditions: Metal can be painted Chain should be coated with oil