The introduction to your report is not part of the IB rubric, but it is part of a scientific paper. At ISB, we expect you to include an introduction for your scientific papers.
The introduction should start with a brief description of the situation being investigated. The relationship you will be investigating should then be described and discussed.
The introduction should give some background information about the theory or models with which your research can be understood, including equations if appropriate. Research which applies to your investigation should be described and discussed. The theory/model/research introduced should be used to discuss the expected results of the investigation. Be as precise as possible in discussing your expected results. If the theory predicts a direct linear relationship, then say so, don't just predict an "increase". If the theory predicts an inverse square relationship, don't just say you expect a decrease. Finally, be sure to cite your authoritative sources (not Wikipedia).
The introduction should also describe and discuss any special lab techniques or processes involved.
Avoid using the word "lab" (In this lab, the...) in the introduction. Use the word "investigation" or "research" instead.
Use "is expected to" rather than "should". ("The rate is expected to increase as the temperature...." is better than "The rate should increase as the temperature....".)
Here is a good example of an introduction.
Here is an example of an introduction with some flaws. Can you see what could be improved?
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