Three of our students recently took part in UEA’s Chemistry Competition. Carla Hill, Kevin Chow and Alex Mallon went with teacher Simon Russell to take part. Here Carla describes the experience:
“We did 3 practicals, all based around drugs and medicine. Each practical was followed by a series of calculations to work out things such as number of moles of substance reacted or the concentration of a particular substance. The practicals were marked based on the accuracy of our measurements and calculations to determine the winner out of the 18 sixth forms taking part.
The first practical was an acid-base titration of citric acid and sodium hydroxide. We had to make the standard solutions of citric acid and NaOH ourselves and use our results to calculate the concentration of the citric acid.
Our second practical was determining the concentration of paracetamol in some paracetamol tablets. We did this by crushing the tablets and making standard solutions of varying concentrations using the powder and acetic acid. We then used spectrophotometry to measure the light absorption of each concentration. This was done by putting a small amount of the solution in a cuvette and putting this into a spectrometer, which gave us a reading. We then had to plot a graph to work out the concentration of our original paracetamol sample. I was put in charge of the main bulk of this one, while Alex and Kevin got started on the third and final practical.
The third practical involved using chromatography to determine the caffeine content in filter coffee. This was mostly done by a machine, but we had to make up standard solutions of the coffee beforehand. Samples were then put into the chromatography machine, which produced a chromatogram of the coffee’s contents. The figures obtained from the chromatogram then had to be plugged into equations for the quantity of caffeine to be calculated.
We finished a good 20 minutes ahead of time, having done our best to gain accurate results, and waited a nervous 45 minutes for the results. Unfortunately, we didn’t place, but we all enjoyed the day, feeling like proper chemists and gaining some good practical knowledge and experience. Mr Russell, however, did manage to win the teachers competition, winning pens, chemistry balloons and a mug. Thanks to Mr Russell for giving us the opportunity to take part!”