The aim of my experiment Essay Example for Free

The aim of my taste EssayEvaluation Although I aroma that my experiment was sound overall, I thought t present were m any(prenominal) points at which the accuracy was not perfect. As I have already stated, my preliminary experiment was not accurate enough to justify world used as my main experiment, mostly out-of-pocket to the fact that I was relying on all the bubbles being the same size, which they clearly werent, however many of the smaller inaccuracies also apply to my main experiment.Firstly, the distance amongst the light sources and the Canadian Pondweed were not heedful to a very high degree of accuracy, especially when you note the fact that the distance should have been measured exactly from the filament of the light bulb to the join of the plant, and it is possible here to welcome a ploughshare hallucination. I estimate that the delusion could have been up to 0. 5cm and I will find the percentage error for the largest and smallest reading using this estimat e Percentage error = possible inaccuracy total reading % error distance 10 5cm 1 50cm It is clear to see that the percentage error is much less for the larger distances.Although I was not actually using the distances as part of my results, I used them as a crisscross for where the lamp was placed each time, as I assumed that the light intensity would be the same each time at a particular distance. Therefore, any inaccuracies in measuring the distances, i. e. if a distance was slightly different when doing the actual experiment from the distance at which I earlier measured the light intensity, an error would ensue. The second major inaccuracy was in measuring the volume of oxygen given off.When reading the syringe there could have been an error of 0.25mm, and again it is possible to find a percentage error. % error volume 3. 57 7ml 50 0. 5ml For the smallest volumes this is clearly a massive error, and to improve this, it would be necessary to do the readings over a longer period of time, therefore increasing the volumes, and in turn trim the percentage errors. Another error would have been due to background light in the vicinity.We tried to reduce this error by closing all blinds in the laboratory, but due to practical reasons, we could not all perform the experiment in a separate room, and we therefore experienced light pollution from other students experiments.This would have had a very marginal aftermath on my results as a whole, but to eliminate this problem completely, it would have been necessary to perform the experiment in a totally dark room. A further inaccuracy was in the waken generated by the lamp. As I have earlier described, temperature has a very noticeable effect on the rate of photosynthesis, and so any increase in the temperature of the pond water would have had serious effects on the accuracy of my results.To ensure this did not happen, I monitored the temperature of the water before and after every reading, to find out that the tempera ture did in fact not rise. It turned out not to be a problem, as over the short period of time taken by my experimental readings, the temperature did not rise at all. However, if I were to extend the time of my experiment to 5 minutes for each reading for example, which would have the effect of reducing other percentage errors, I would have to find slightly course of keeping the temperature constant.One way of doing this would be to place a perspex block between the lamp and the plant, which would absorb most of the heat, while allowing the light energy to pass through. As I mentioned in my planning, carbon dioxide concentration could have been an error in the experiment, however, I feel that due to the short period of time taken, there is very little chance that the concentration would ever have been so low as to have become the limiting factor.Again if I were to carry out the experiment over a longer time period, it would have been necessary to make sense sodium hydrogen carbon ate to the water to increase the carbon dioxide concentrations. The last inaccuracy, though a small one, was in the time keeping. The main problem here was in when to begin the minute. If for one reading, the minute was started just after one bubble had been produced, and in another reading it was just before, this could have had a veto effect on the accuracy of my results.I therefore ensured that in each case I started the stopwatch just after a bubble had been produced, therefore heightening the accuracy. Overall, I felt that due to the small volumes of oxygen involved, my experiment was not as accurate as it could have been, however I recall it was accurate enough to support and justify my hypotheses. Improvements could have been made as I have stated, mainly by simply increasing the time taken. However, due to practical time constraints in taking the readings for my investigation, and some consequential problems relating to time extension, I could not in fact make these adjus tments.The other obvious way of increasing the reliability of my results would be to take many repeat readings and find an average. To extend my enquiries into the rate of photosynthesis, I could perhaps try to link in some of the other limiting factors to the same experiment, as well as investigating them in their own right. It could also be interesting to explore the effects of aslant lights on the rate of photosynthesis, which could lead to the question of whether or not other types of light, such as fluorescent lights or halogen lights, would have a different effect on the rate of photosynthesis.