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PREPARED BY NAME ID NUMBER NORHAFIZAH BINTI NORDIN D20101037456NURSYAHIRA AYUNI BINTI AHMAD D20101037457 ZAMRI AIN NABILA BINTI ABD. MALEK D20101037463
TITLE:THE EFFECT OF SALT ON THE RATE OF CORROSION
ENGAGE Nail A Nail B• These two nails were located at same place.• Nail A was immersed in salt water while nail B was immersed in plain water.• Which nails will more corrosive?
Questions Which nail is more Why? corrosive? From thesituation, what Can you happen to explain? both nails?
EMPOWERStopper with Computerdelivery tube Test tube Salt water Nail A Retort stand Figure 1: Design of the experiment
Plan of the experimentObjective• To investigate the effect of salt on the rate of corrosion.Hypothesis• Salt water increase the rate of corrosionVariables• Manipulated variable: Type of water• Responding variable: The rate of corrosion• Fixed variable: Temperature
Plan of the experimentApparatus• Nails• Salt water• Plain water• A delivery tube• Cork• Pressure sensor• Retort stand
Plan of the experimentMethods1. Prepare 2 test tubes labeled A and B.2. Set up the apparatus as shown in Figure 1.3. Place a nail in each test tube.4. Pour salt water in test tube A and plain water in the test tube B.5. The water is pored until it overflow from the test tube.6. Insert the stopper with delivery tube.7. Make sure there is no air bubble in the test tube.8. Connect the pressure sensor at delivery tube.9. The pressure sensor is connected at computer.10. Measure the pressure change of both test tube over 7 days.
Plan of the experimentResult The rate of corrosion 2.5 2 Pressure (Pa) 1.5 1 salt water plain water 0.5 0 0 2 4 6 8 Days
Plan of the experimentDiscussion• Based on the result, nail A that immersed in salt water is more corrosive than nail B that immersed in plain water.• This is because, oxygen present in water and salt causes corrosion. Salt is hygroscopic in nature and it attracts the water. Water is required for corrosion and salt speeds up the process.• The salt speeds up the corrosion by improves the capability of water to carry electron through redox reactions.• Rusting in metals undergoes an electrochemical process in which iron loses electrons by oxidation causing the water to break into hydroxide ions and oxygen. The metal that has oxidized reacts with the hydroxide ions and oxygen to form metal oxide. These salts remain even if the water is gone and they again start rusting whenever they come in contact with moisture.
Plan of the experimentConclusion• The salt water increase the rate of corrosion compare with plain water.
ENHANCE A- House at Pantai Teluk Lipat B-House at Putrajaya• From the above pictures, predict the condition of gate after 10 years based on the locations?• Give the reasons to support your predictions.• Explain the changes process.
EXTENSION Ship A Ship B• According to the pictures, ship A is more corrosive than ship B.• How to reduce the ship A from keep corrosive? Explain.• Does humidity also affect the corrosion process? If yes, give the explanation.