2. A black marker was used to mark a black cross on a white sheet of paper. This was to help with measuring the time (dependent variable).
3. A thermometer was placed on the table to measure the room temperature.
4. 0.15mol/L sodium thiosulphate solution (Na2S2O3) and 3mol/L hydrochloric acid (HCL) were poured into two separate 50 ml beakers, and the two beakers were transported to the experimental table for convenience.
5. 25 ml of 0.15mol/L sodium thiosulphate solution were measured in a 25 ml measuring cylinder. Pipette was used to transfer the solution from beaker to the measuring cylinder for accuracy.
6. 4 ml of 3 mol/L hydrochloric acid were measured in a 10 ml …show more content…
Three conical flasks with HCL solution and three conical flasks with Na2S2O3 solution were all put into the same plastic container for 2 minutes. This was to make sure the flask and solution had the same temperature as planned.
(Controlled the temperature)
20. The temperature was recorded down before the experiment was stared, and the plastic container was placed on top of the black cross. The person who did timing was ready to start the stop watch.
21. The same procedure was repeated from step 11 to step 14.
22. The kettle of hot water and ice were used to regulate other temperatures (0ᵒC, 10ᵒC, and 40ᵒC).
23. 9 experiments were done on the three temperatures (0ᵒC, 10ᵒC, and 40ᵒC) included 3 trials for each temperature.
24. All of the procedures were repeated as done for the previous three experiments.
25. All of the equipment used were washed and cleaned carefully, and returned to the appointed places.
• Each of the 5 different independent variables was repeated for 3 times as 3 trials.
• The conical flasks were placed in the water baths for two minutes before the experiment was started.
• Hot water and ice were added to the plastic container whenever there was change in