2019 Year 12 IB Extended Essays

M ETHODOLOGY

The method was adapted from a pre-existing experiment conducted by the Royal Society of Chemistry . Method applied for Cobalt (II) Chloride: 1. Place five test tubes into a test tube rack in order to ensure stability. 2. With the use of a weighing dish and an electronic balance weigh five sets of gelatine, each weighing 1.5000g. 3. Add gelatine powder into five different 100cm 3 beakers. 4. Measure out 2.5000g, 3.0000g, 3.5000g, 4.0000g, 4.5000g of cobalt (II) chloride. 5. Add cobalt to beakers with gelatine powder. Ensured to label each beaker the appropriate mass present of cobalt (II) chloride. 6. Add 50cm 3 of deionised water to each beaker. Quantify using a 100cm 3 measuring cylinder. 7. Warm beakers on hotplate at low heat, between 35˚c and 45˚C. Stir at 20 sec intervals until solution becomes clear. 8. Label test tubes with the different masses of cobalt (II) chloride (2.5g, 3.0g, 3.5g, 4.0g, 4.5g) using the masking tape and whiteboard marker. 9. Pour solution carefully into test tubes which corresponded to mass, ensuring to leave approximately 5cm of space in the test-tube. 10. Cover all test tubes with parafilm. 11. Complete steps 1-10 twice more to have 15 total test tubes. 12. Leave substance undisturbed for 1 day or until the formation of gel is noticeable. 13. Carefully pour approximately 50cm 3 808 ammonia on top of gel until test tubes are full. 14. Covered test tubes with parafilm and remain undisturbed for a week-long period.

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