Finding the number of Moles of Magnesium and Oxygen in Magnesium Oxide
Table of Results:
Calculations for Empirical Formula:
- Number of moles of Magnesium in Magnesium oxide:
Moles/mol = Mass/g ____
Relative atomic mass/ g/mol
Moles/mol = __ 0.13g__ = 0.00541 moles ( 3sf)
24g/mol
- Number of moles of Oxygen in Magnesium oxide:
Moles/mol = ____Mass/g______
Relative atomic mass/ g/mol
Moles/mol = ___0.02g__ = 0.00125 moles ( 3sf)
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Peer Reviews
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Quality of writing
Minor grammatical errors seen in places. For example in the Rouge results and observations section, 'effected' should be 'affected.' The layout of the analysis of the experiment could be better presented. This is because the titles do not look tidy as they are too long, and the text is quite long-winded and if the information was presented in tables where possible this would look a lot tidier and be easier to read. Other spelling, grammar and punctuation is fine.
Level of analysis
No method is included, and this should be included so the candidate can discuss potential things that may have gone wrong in the experiment and that could have been improved. The candidate is consistent in decimal places seen in the table which is essential for accurate calculations. The candidates working out are correct and presented in a clear way with solutions presented in bold which would help anyone marking this piece to look exactly for what they need to mark it. The candidate points out potential problems with the experiment well, but alongside this I would have included potential improvements as this would have indicated a higher level of understanding about the experiment and whilst this is included in the evaluation, to provide this alongside the problem would present better. The observation described is very long winded, and it would be much easier to mark if the candidate presented this in a table, using a description of the strip at the beginning, and then at the end rather than a long drawn out description. The evaluation itself is good, and points to possible improvements to the experiment.
Response to question
The response to the question is well done. The candidate does not include a method, and the reasons for doing so are discussed below. The calculations made by the candidate are correct, and the further analysis of the experiment in the evaluation and sources of error sections are done to a very high level because they point out a range of different problems and possible solutions to a few of them.
