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Toolooa Teams Win 4 Gold and 2 Silver Medals in National Final of Titration Competition

31/10/2013
 
Toolooa Teams Win 4 Gold and 2 Silver Medals in National Final of Titration Competition.
 
 
The Royal Australian Chemical Institute (RACI) Australian National Chemical Analysis (Titration) Competition has been running since 1984. Acid-base titration is a method in chemistry that allows quantitative analysis of the concentration of an unknown acid or base solution. This technique is used for chemical analysis in nearly every working laboratory.
 
The competition has two stages – the first round involves Regional Competitions in each state. The teams that place 1st, 2nd or 3rd in the Regional Competition are then invited to take part in the National Finals.
 
This year there were 14 teams competing in the Central Queensland competition, from as far south as Bundaberg and as far north as Rockhampton.
Toolooa State High School entered two teams in the regional competition which took place on Thursday the 8th of August. Team 1 (consisting of Josephine Tucker, Kahlia Mallet-Jackson and Kahla Button) obtained an excellent result and won the regional competition.
 
Team 2 (consisting of Joshua Reilly, Elora Ghea and Sarah Crail) were not far behind then, taking out 3rd place in the regional competition.
As both of the Toolooa teams finished in the top 3 positions, both teams were invited to participate in the National Final which took place on Thursday the 24th of October.
The National Finals are even more demanding that the regional competition.  Students have just three hours to complete the complicated analysis and calculations. Each year only the best teams in the Finals achieve remarkable accuracy in this quite difficult exercise.
 
The finals are much more demanding that the regional competition. Each Finalist is given two samples. One sample contains about 0.4 g of the weak acid potassium hydrogen phthalate (KHP), accurately weighed. The student is told the amount in this 'standard sample'.
 
The other sample, the 'unknown' also contains about 0.4 g of potassium hydrogen phthalate, also accurately weighed, but the entrant is not told this amount. A little insoluble barium sulphate is added to the unknown sample as well.
The entrant has to determine the amount of acid in the unknown sample. They firstly have to carefully dissolve the known sample and dilute it to 100 mL. This is the standard solution they will then use to accurately determine the concentration of an unknown solution of sodium hydroxide by titration.
 
The entrant must then dissolve the unknown KHP sample, but must first carefully filter out the insoluble barium sulphate before diluting the solution to 100 mL. They then titrate this against the sodium hydroxide solution in order to accurately calculate the amount of KHP that was in the sample.
 
The score a student receives is based on how accurate the student’s answer is. This means that the lower the score, the better the result. The student with the best individual result in the National Final was Josephine Tucker. Here excellent score of 3 means that she was very accurate. Her answer was 0.00261 moles and the actual answer was 0.00264 moles. This is an excellent result and has earned Josephine a gold medal. Any score less than 20 are considered excellent. Three other students also obtained excellent results. Well done to Joshua Reilly with a score of 8, Elora Ghea with a score of 9 and Sarah Crail with a score of 18. They will all also receive gold medals.
 
Kahla Button and Kahlia Mallet-Jackson also had some good results and will receive silver medals.
 
The National Final is a team competition however. Team scores are allocated based on the accuracy of each member. A huge congratulations to Team 2 (Joshua, Elora and Sarah) who were awarded a score of 469. Any score less than 1000 is considered excellent.
 
The school and students would like to thank Mrs Heather Warren and QAL. Mrs Warren has provided invaluable assistance by providing chemicals for practice sessions and by attending practice sessions alongside Chemistry teacher Joanne Cooper in order to assist the students in their preparation for the finals.
 
Well done to all of the students involved. They have devoted a lot of time to practice sessions and it is great to see that their hard work has paid off.
We will have to wait a few weeks to find out what place is allocated in the National Competition to Team 2.

With a score this good, we are confident that they will make the top 20 list.
We look forward to finding out their final ranking.