Top of the Bench
On Thursday 12th January, four girls from College: Fran Neale, Maddy Culhane, Amy Strain and I travelled to Bristol to compete in the Royal Society of Chemistry’s competition, ‘Top of the Bench’. When we arrived we were given lab coats, safety goggles and badges. During the first hour we were given the task of completing two practicals. Amy and Fran performed the iodine clock experiment while Maddy and I performed an experiment in which we added solute to an unknown solution which we then dissolved it with a magnetic stirrer. We soon discovered that the solute turned the solution red before turning the solution light pink. Our job was to time how long it took for the solution to go from the darkest red to the lightest pink during five cycles and to discover when the cycle stagnated. We also had to determine which ions caused the colouring. Fran and Amy performed the iodine clock experiment in which two solutions are added together and, after a certain length of time, turn black. The task was to make this occur after precisely a minute. In order to do this they had to either increase the concentration or dilute either one or both of the chemicals.
We then had a very short break and went back into the lab for the second experiment. We had to work out the percentage of sugar in three fizzy drinks; to do this we weighed the mass of the three sucrose solutions with different concentrations. To ensure we were accurate we used a pipette. After this we were asked to work out what the 10% and 5% sugar solution would weigh after which we drew a graph of our results. Next we measured the amount of sugar in each of the fizzy drinks by weighing them. Once we had worked out the mass of the drinks we were able to work out what the percentage of sugar in each drink was, by using our graph.
Whilst we were waiting to hear who had won we watched a fascinating chemistry demonstration which involved a nitrogen waterfall, dry ice and various polymers mixed together to make slime. My favourite bit, however, was when I saw a piece of rubber tubing dipped in liquid nitrogen – which is so cold that the rubber tubing became hard and brittle.
At last the results were ready. Overall we came fifth, but more importantly we all had a wonderful experience, and used equipment we wouldn’t normally get to use in the classroom. We would like to thank Dr Gamblin for organising the trip and Dr Stables for taking us to the competition.
Rachel Manson, LC3
Article Created 17/01/2012