I am investigating the reaction of solid Calcium Carbonate with Hydrochloric Acid,The word equation for this is,CaCo3 + 2HCL ? CaCL2 + CO2 + H2OI aim to produce a valid set of results to produce a good graph for evaluation.What I Already KnowA reaction occurs when particles collide. This process is based on random particle movement. So therefore, the more particles you have in a space, the more likely they are to collide. Therefore making the reaction accelerate.
This theory can be proved if you compare the rates of reaction with marble in hydrochloric acid. If the acid is of a higher concentration, the reaction will be quicker.Also if the particles have more energy, they will be travelling faster, making them collide more frequently.PredictionWhen the concentration of acid increases, more gas will be given off faster. I know this from my trial experiments.MethodSince I will be working with acid, I will wear safety goggles while conducting the experiment.I will use 1gram Marble chips that are all ground down to roughly the same size, and I will use 20cm3 of HCL of different concentrations ranging from 0.
4M – 2MI can measure the reaction by how much gas is given off. When the experiment takes place, I will take the reading after 2 minutes to get a graph for the results.To be sure I can rely on my results I will repeat he experiment three times if necessary, because there is chance of inaccurate results for many reasons.e.g. 1.
Temperature2. Inaccurate Measuring3. Unbalanced Scales4. Mass of CaCo35. Molar of acidI learnt from the trial experiments, some rough timings to go by in the real test. I don’t think it is necessary to have the experiment go over two minutes, so I will cut it off then.
ResultsMy Results are as follows:Test 10.4M Amount Of Co2 Lost = 0.120.8M Amount Of Co2 Lost = 0.191.2M Amount Of Co2 Lost = 0.221.
6M Amount Of Co2 Lost = 0.312.0M Amount Of Co2 Lost = 0.32Test 20.4M Amount Of Co2 Lost = 0.
130.8M Amount Of Co2 Lost = 0.181.
2M Amount Of Co2 Lost = 0.211.6M Amount Of Co2 Lost = 0.272.0M Amount Of Co2 Lost = 0.34Test 30.
4M Amount Of Co2 Lost = 0.140.8M Amount Of Co2 Lost = 0.151.2M Amount Of Co2 Lost = 0.231.
6M Amount Of Co2 Lost = 0.292.0M Amount Of Co2 Lost = 0.35Average Results And Graph/Table0.4M Amount Of Co2 Lost = 0.
130.8M Amount Of Co2 Lost = 0.171.
2M Amount Of Co2 Lost = 0.221.6M Amount Of Co2 Lost = 0.292.
0M Amount Of Co2 Lost = 0.34Mole Of AcidMass Of BeakerBeaker + HCL + AcidMass after ExperimentMass LossTime Of Experiment0.498.37117.52117.
390.132 mins0.898.37117.68117.510.172 mins1.
06117.720.342 minsAs we can see from the graph my results gave a good line of best fit which we can use to gather other results like the mass loss of CO2 when we add water ( 0M ) instead, this would give us about 0.07 grams of CO2 lostAnalysis of ResultsFrom the experiment, I have found that an increased concentration of acid increases the rate of the reaction.I think that the best way of displaying these results was by drawing a scatter graph with a line of best fit. In it, I have used the average of the three sets of results.
The pattern I can see is that the higher the concentration of acid the greater the mass loss is. We can see this because the line of best fit has a positive coloration.The cause of this is that at the start of the reaction, there is the most amount of acid molecules that are colliding with the CaCo3 and eventually this neutralises and starts to slow down which is why the less acid you have the quicker this happens because there isn’t enough acid to react with.EvaluationIn my opinion the investigation went OK. I think I did take a sufficient amount of readings but of course it would have helped if I had another set of results but you could say that for every experiment that you do because it would give you a better average. I think that doing 3 runs was a good idea because some errors were made which affected the results, but by averaging the data obtained, the results were more precise.
There was one anomalous result that I encountered but we did a rerun and quickly found out that is was just a weighing error. As the experiments were done on different days, the results could have been affected due to a different room temperature, or humidity. Although I think that these differences are negligible because the weather was the same both days ( roughly ).