Table of results:
We can then calculate the percentage of the lost gas as follows:
= =
Data analysis:
From the results of the experiment we were able to calculate which of the three reactions is correct. We know that the correct reaction will give a 37% loss in mass. The lost mass is made up of the gases released from the compound. We can then first in theory try to predict the expected masses of the different elements in each of the three equation by using the following formula: n =
Reaction A
From these results we can then calculate the percentage of the mass which is made up by the gasses.
= =
This shows that in reaction A the gasses released make up 63 percent of the total mass. This means that this equation is incorrect.
Reaction B
From these results we can then calculate the percentage of the mass which is made up by the gas.
= =
This shows that in reaction B the gas released makes up 52 percent of the total mass. This means that this equation is incorrect.
Reaction C
From these results we can then calculate the percentage of the mass which is made up by the gasses.
= =
This shows that in reaction A the gasses released make up 37 percent of the total mass. This means that this equation must be correct as it was mentioned in the aim that the expected loss in mass in 37%.
Conclusion and evaluation:
After conducting these experiments and calculation the expected percentage, we can see that our result was very close to the expected result. We calculated that the lost gas had a percentage of 35. That was a difference of only 2% from the expected result from reaction C The difference can be due to the uncertainties and errors that might have occurred during the experiment.
One uncertainty is the scale we used. It could only measure with a precision of 0.01g. Though this is rather low, one can not be more precise with the experiment. It is also possible that we made some human errors during the experiment. We could simply have misread the values on the scale, or have been too quick in reading the scale as was the case during our experiment where we at first misread the mass of the crucible. There could also have been an error while heating the baking soda.
We could have made the experiment more accurate by allowing the baking soda to heat for a reasonable amount of time. This would let as much of the gasses to evaporate as possible. It is also an option to use a more accurate scale. Another important thing in this experiment is making sure that the crucible we used was clean and without any leftover particles from previous experiments. And lastly one should always while conducting any experiment be careful when reading and recording the values and data necessary in the experiment.
