Iron Nails Experiment

Aim:
To investigate, the corrosion of Iron nails in different levels of Sodium Chloride (NaCl) concentrations.

Hypothesis:
An increase in the level of concentration of Sodium Chloride (NaCl) will increase the level of corrosion on the Iron nail.

Equipment:  Safety Glasses
 Safety Apron
 x4 Iron nails
 x4 4.5ml Test Tubes
 x4 25ml Beakers
 Distilled Water
 Ruler
 Pipette
 Digital Bench Scale
 Stirring Rod
 Watch Glass
 Test tube holder
 x8 Labels
 10ml Measuring Cylinder
 Sodium Chloride (NaCl) Method:
1. Measure out 12ml of distilled water using a 10ml measuring cylinder and pour into a 25ml beaker.
2. Weigh out 0.6g of Sodium Chloride onto a watch glass with a Digital scale and pour into the beaker in step 1.
3. Stir

To minimise this risk handle the nails carefully and if you drop it, pick it up straight away.

Results:
The results that will be collected include;
 The weight of the Iron nails before and after the experiment. o These results will be collected by weighing the nails on a digital bench scale.
 The lengths of the iron nails before and after the experiment. o These results will be collected by measuring the nails with a ruler.
 Photos of the Iron nails before, during and after the experiment. o These results will be collected by taking photos on a camera.
 Written observation of the Iron nails before, during and after the experiment.

Discussion:
Throughout this practical experiment both chemical and physical changes had occurred, these were observed by the changes in the colour of the solutions, and on the iron nails and by the precipitation of an insoluble solid forming. The iron nails, when put into the sodium chloride solution immediately started to chemically react together. This reaction rapidly caused the iron nails to form an orange/brown coating and for an element to precipitate at the bottom of the test tube, an orange/brown coating also formed around the test tube near the top of the sodium chloride solution. Suspended throughout the solution were small dark particles and also dark particles

Another error could have been that the measured amount of distilled water in the beaker may have been inaccurate due to an incorrectly measured and marked measuring cylinder. This would have affected the concentration of the sodium chloride solution and in turn made the nail corrode at a different rate then what was expected. An error concerned with the pipettes could have been that different pipettes may have been used throughout the practical; this would have produced an issue as the drop sizes of the used pipettes may not have been the same and caused more solution to be in one test tube then the others. Another error could have been that over time some of the water in the solution could have evaporated, this would have caused an increase in concentration of the negative and positive ions and in turn speed up the corrosion process