Evaluation.
In my opinion the experiment was very successful.
Firstly I want to write about the quality and accuracy of my results. I kept a fair test and made sure I was using correct equipment in the appropriate way. I have also made sure the temperature, the surface area and mass of potassium carbonate (K2CO3 ) were kept the same during the whole experiment. I have also made sure I was using appropriate amount of hydrochloric acid for each experiment. Even though, there could be a small error caused by the human reaction, I made sure I was taking the readings from the stop-clock accurately. I’ve repeated my experiment, in order to find out the average results and make them more accurate. Also, when measuring the mass of potassium carbonate, I have always used the same scales and made sure they were always starting at 0g at the beginning. I’ve made sure I was wearing the white coat and goggles and made sure everything was safe.
From the graph and results table it is evident, that the average time of reaction increases as the amount of hydrochloric acid increases. From the results it can be concluded, that the time of reaction is dependent on the amount of hydrochloric acid being produced.
Overall, I have obtained fairly accurate results, which satisfied me, proved my predictions, and which also helped me to plot quite informative graph and results table. Also, I think I gave enough time in my experiment for the reaction to happen. However, as I was carrying out my investigation I noticed, that there were some problems with accuracy in my experiment, and that there were few things, which I could improve. The first thing I think I could possibly improve next time is measuring of the amount of hydrochloric acid more accurately. Slight differences could have caused some changes in time, which could slightly affect the rate of reaction. The second problem which could affect the time of reaction could be my own, human reaction. Although I tried to pay more attention when taking the readings from the stop clock, there were some slight changes. I can still improve on this, but my own reaction is one of the independent variables in this experiment, which I’m not able to change much. Also, my experiment took place in the chemistry laboratory. Although I’ve tried to keep the temperature in my experiment the same, there is a possibility, that during the experiment there were some slight changes in the temperature in the classroom, which could affect the rate of the reaction. As the result of that, the results I’ve gained in this experiment could slightly alter. The solution for this problem is to use a special thermometer, in order to make a control of temperature in the room and to make sure there are no anomalies taking place in my experiment. The third problem, which could occur and cause anomaly in my experiment, was the accuracy in measuring of the mass of K2CO3 . When measuring the amount of potassium carbonate, I was using special electron scales, but even though I made sure they were always starting at 0g point at the beginning, they could still sometimes be wrong. All these factors have caused some anomalies and inaccuracy in my experiment. However, I will be able to improve it next time.
The data collected from this experiment indicates, that even though there were some slight changes in the experiment, the results I’ve gained were relevant and proved that my prediction was right. From this experiment I have learnt, that next time I do it, I will need to be more accurate when measuring and recording my results. Also, I think that by trying using a wider range of concentrations of hydrochloric acid next time, it will be possible to find a wider range of more varied and accurate results. If all the factors, which caused an anomaly in this experiment don’t occur next time, I’m sure the results will be more accurate and predictable. Making sure that the previous errors don’t take place in the next experiment, will help to maintain higher quality evidence, and as a result, higher quality of experiment.
Overall, I’m satisfied with the results I have gained in my experiment. I think that from my experiment I have gathered enough evidence to prove, what I have predicted before starting it, that as the concentration of hydrochloric acid doubles, the rate of reaction between hydrochloric acid and potassium carbonate doubles and time taken for the reaction to happen halves. Therefore, I think that my experiment was successful.