I predict the experiment where we change the temperature of the solution, will react the fastest, because the particles are moving faster and will have greater effect on the limestone. Where as the concentration of acid experiment, there maybe more acid particles, but they are not moving around as fast and therefore not having as big reaction. As we increase the factor the rate will increase. I predict that if we double the temperature of the solution the rate of reaction doubles as well.
Diagram,
Method,
For the temperature experiment we will;
- Weigh the beaker.
- Then heat 20cc of hydrochloric acid to the desired temperature.
- Then add 5grams of calcium carbonate (limestone)
- Put on the scales and note the weight of the beaker and solution per minute.
- Repeat the experiments for all of the temperatures.
- Then work out the weight of the solution by subtracting the original weight of the beaker.
For the concentration of the acid experiment;
- Weigh the Beaker.
- Collect 20cc of hydrochloric acid at concentration of 1M
- Then add 5grams of calcium carbonate.
- Put on the scales and note the weight of the beaker and solution per minute.
- Repeat the experiment for all of the concentration levels.
- Then work out the weight of the solution by subtracting the original weight of the beaker.
Results,
For the temperature experiment
30
40
50
60
70
For the concentration experiment
1M
2M
4M
Conclusion,
In our first experiment, as we increased the temperature, the rate of reaction also increased. The rate of reaction increased fairly dramatically from 30°C to 60°C.
However at 70°C the rate of reaction decreased. This may be the result of increasing the temperature so much that the particles are no longer efficient.
In our second experiment, as we increased the concentration of the acid the rate of reaction also increased. The rate of reaction did not increase as dramatically as in the temperature experiment. This is because, although when the concentration is increased the number of particles increases, they do not move as quickly as when we increased the temperature. This means that in the concentration experiment the particles do not bang into the limestone with as much force and therefore do not break it down as well. This shows why the temperature experiment has more effect then the concentration experiment.
This matches what I initially thought in my prediction.
Evaluation,
From my results there were no readings that were necessarily wrong, but there were instances when other factors could have affected them. My main example of this is in our Concentration experiment where the decrease in weight for the first minute using concentration 2M was dramatically greater than anywhere else in the testing. This could have been an error in collecting data, or there could have been a factor, such as the room temperature, that made a difference.
If I was to do this experiment again I would:
- Repeat the experiment more times to get a more accurate average.
- Controlled the temperature of the room, so that it didn’t affect my results.
- Been more thorough when noting down readings.
- Choose more suitable scales for my graphs to be drawn at.