2. Methods

Procedure

  1. Prepare 5 moisturisers samples that each have a different main ingredient and 6 petri dishes. 5 will be needed for the experiment and 1 will be needed for control.
  2. Label the moisturisers and the petri dishes accordingly from 1 to 6.
  3. Create a chart in the form of a table in the lab booklet to record down the results. The chart should include the time (in hours) and the weight (in grams) each time a recording is taken.
  4. Boil water in a 500 ml beaker on a heating pan.
  5. When the water starts to boil and bubbles are formed, turn off the power of the heating pan and let the water cool down for 1 minute.
  6. Pour 400 ml of the hot water into a 1000 ml beaker.
  7. Open one packet of Jell-O powder and empty the entire packet into the 1000 ml beaker.
  8. Stir the powder evenly into the water using a glass rod stirrer until it dissolves.
  9. Pour 400 ml of cold water into the 1000 ml beaker after stirring.
  10. Stir for another 2 minutes.
  11. Open the lids of the petri dishes.
  12. Pour the Jell-O water into the petri dish until the petri dish is 2/3 full.
  13. Repeat Step 12 with the remaining petri dishes.
  14. Put the lid back onto the petri dish.
  15. Repeat Step 14 with the remaining petri dishes.
  16. Get a basket and put all the petri dishes into the basket.
  17. Put the entire basket into a refrigerator and leave it there for at least 12 hours for the Jell-O to turn into the jelly form.
  18. Collect your Jell-Os the next day from the fridge and take 5 of them out  of the basket while leaving the control setup in the basket. (Moisturizer will not be applied on the control setup.)
  19. Wash your hands thoroughly to make sure they are clean.
  20. Take moisturizer 1 and squeeze out an appropriate amount onto your hands. Next, apply it onto  the Jell-O in petri dish 1 in an orderly manner using your finger. (Please remember to wash your hands before applying another moisturizer for another petri dish)
  21. Repeat step 20 for the remaining moisturizers.
  22. Put the 5 petri dishes with the moisturizers applied back into the basket.
  23. Take the basket and put it back into the fridge.
  24. Wait for 30 minutes before taking your first recording of the Jell-O’s weight.
  25. After taking your first recording of the Jell-O weight, proceed to take the remaining recordings  every 24 hours .
  26. Repeat the experiment if the results collected is inconsistent.


Risk Assessment and Management

  1. There will be the process of heating the water , in which the students may scald themselves. To prevent this from happening, there must be a teacher supervising the process or helping out with the heating.The risk assessment for  this scalding is medium risk level and tolerable with a scoring of 7 marks.
  2. There will be the use of heating causing the beaker or plates to become hot, in which the students may burn themselves. Therefore, a wooden/plastic spoon or a glass rod stirrer should be used to prevent the conduction of heat.The risk assessment for this  burning is medium risk level  and tolerable with a scoring of 6 marks.
  3. When handling the beaker on the hot pot, the students may  burn themselves too due to  high heat,thus the use of mittens is required so that they can protect their hands.The risk assessment for this  burning is low risk level and broadly acceptable with a scoring of 4 marks.

Method of analysis of results
We will only be recording the weight of the Jell-O using a weighing scale and not the height as we think that the height of the Jell-O may not show accurate and reliable results due to condensation of Jell-O droplets along the side of the petri dish and the lid of the petri dish.

No comments:

Post a Comment