How the rate of reaction of Hydrochloric acid and Sodium Thiosulphate is affected by concentration? - page 2
Keywords: data analysis
By shaz on 08/02/2010
Level: GCSE Key Stage 4 (Years 10-11)
Page Number: 2 of 3 pages: 1 2 3
disappear decreased significantly. This could have been due to some form of error since I did not repeat the experiment. However, I think that it is due to a more detailed scientific reason. If I was to do this again I would investigate further by using a larger range of volumes. For instance, I would do 5cm³, 6cm³, 7cm³, 8cm³, 9cm³, 10cm³ instead of going up in volumes of 5.
I should have also repeated the tests at least three times and taken an average to make sure my results are more reliable
I think I should have used a more efficient method to measure and record the time taken for the cross to disappear. I found it very difficult to maintain accuracy when I had to stop the clock at the sudden instance where the cross had disappeared. Also in lower concentrations the cross disappeared in some areas of the flask but it could still be seen in some small areas. This made it quite hard to record and to keep the test fair. I would use a larger range of time so I could have got more results and this would have resulted in a better overall result.
The result for 15cm³ was an outlier because it did not the fit on the curve of best fit. The result may have turned out anomalous because of human error, or maybe because I measured the substances wrong. It may have even been
because I did not clean the apparatus properly. It could also be because of the inaccurate equipment I used or because I did not read the time correctly or record it properly. It could also be because I converted minutes to seconds inaccurately. Also, this could have been a result of not cleaning the apparatus or drying it effectively.
I believe my evidence is unreliable because time was not measured precisely. The equipment was not cleaned effectively and more importantly I did not do any repeats.
I believe my evidence is insufficient to support my conclusions for the
because I didn’t repeat the experiment at least three times therefore my evidence is classed as unreliable. However, the procedure I used is repeatable. I think my results are also unreliable because there is an anomalous result.
Further work to provide additional relevant evidence could be to do the same experiment again but make slight alterations to it by using hydrochloric acid as the variable
Last 5 comments…
There have been no comments posted for this article, but you need to register if you want to be the first!