Teacher only page

Choosing the research question

Whose responsibility is it?

The key to the Individual Scientific Investigation is the research question. Without a good research question the student will be unable to address the internal assessment criteria effectively. Many IB chemistry teachers will have supervised Extended Essays in chemistry so will have experience in dealing with research questions. One of the roles of the EE supervisor is to “Discuss the choice of topic with the student and give particular help in formulating the precise research question so that it is sharply focused.” Students choosing to do their Extended Essay in Chemistry are usually motivated with an enthusiasm for the subject. Even so it is sometimes difficult for EE students to formulate a good research question (see the EE page on framing the research question) and the supervisor only has to deal with a relatively small number of students.

With a whole class of students, some of whom may not be as motivated as your EE students, it may be a real challenge to ensure that all your students come up with their own research question for the Internal Assessment and yet that is exactly what the IB requires. The official IB teacher’s support material (TSM) (available from My IB) states clearly that the formulation of the research question for the Individual Scientific Investigation is the student’s responsibility. Teachers may suggest possible topics and approaches to formulating questions but cannot allocate specific research questions to study.” What teachers are expected to do is to guide their students to ensure that their research questions are commensurate with the level of the course and are compatible with the assessment criteria.

Direct student access

Note that students have direct access to a version of this page written specifically for students (as opposed to teachers) at Choosing the research question  in Complete course for students.

Advice to give

You will need to advise them carefully about how to choose a suitable research question. I think the best approach is not to leave it until the start of the ‘ten hours' allocated specifically for the Internal Assessment but to instil in them in what will be required right at the start of their two-year course.

As they cover the practical scheme of work they will need to know:

1. When they eventually do the Internal Assessment they will be required to come up with an investigation that matches the assessment criteria. This effectively means that:

  • it should show personal significance, interest or curiosity.
  • the research question can be clearly described
  • it will produce sufficient relevant quantitative and qualitative raw data to support a detailed and valid conclusion.

2. The investigation can take many forms. It can include, for example:

  • a practical laboratory investigation
  • use of a spreadsheet to analyse and model
  • extraction of data from a database and then analysing it graphically
  • combination of spreadsheet/database work with a practical laboratory investigation
  • use of an interactive and open-ended simulation

As your students learn the necessary skills through the practical scheme of work discuss with them how each practical might be used to provide the basis for an investigation. Get them to consider unresolved questions and/or ways in which the techniques could be altered or extended to cover other possible areas to explore. For example, when calculating ΔH⦵ for the redox reaction between zinc and copper(II) sulfate it is usual to assume that the solution has the same specific heat capacity as pure water. How valid is this assumption? A student could investigate this by using an ordinary household microwave oven. They would need to pass the same amount of energy through the same mass of solutions containing different concentrations of a salt (independent variable) and measure the temperature rise (dependent variable) and hence determine whether the specific heat capacity changes. This example also illustrates that many of the best investigations can be done relatively quickly using simple apparatus.

A microwave oven provides a simple, quick and efficient way to perform experiments
on the polarity of molecules and on specific heat capacities.

‘Hands on’ or ‘hands off’?

1. ‘Hands on’

If a student chooses to do traditional practical work then it may be worth looking at the techniques that are readily available in a school laboratory and giving one example of a topic that could be investigated using each technique. I have in fact already made a list on page 179 of my Study Guide, as this is an approach sometimes used for Extended Essays. Some typical techniques (or equipment that could be used) include:

Titration – acid-base and redox
Extension or refinement of a standard practical
Chromatography
Calorimetry
Use of a pH meter
Electrolysis
Voltaic cells
Microwave oven
Polarimeter
Data logging probes
Visible spectrometer (or colorimeter)
Gravimetric analysis
Microscale

Note that some of these could be used at home using simple apparatus and chemicals that could be bought in local shops. For an example see James Midgley's video  How do to chemistry with your iphone.

2. ‘Hands off’

This may seem an easier option for students but may in fact be more difficult as it is harder (but not impossible) to show personal engagement. They should probably try to find their secondary data from a variety of sources (rather than a single source) and then process it in a way that has not been done before. For example, students will have learned that they should compare the values they obtain in their own experiments with the literature values. They are encouraged to give their own values together with the degree of uncertainty and yet when they look in the data book no uncertainties are given. If they look in a different data book often a different 'literature value' is quoted also with no associated uncertainty – so which is the ‘true’ value and how accurate is it? An interesting investigation might be to compare values from different data sources (see Measuring energy changes for an example) to determine how reliable ‘the literature values’ actually are.

3. ‘Hands on and off’

Possibly the most satisfying investigations are those that combine primary data generated by the student with secondary data that the student has researched from elsewhere. For example, they might determine the percentage of copper in a coin and then research the literature to find how the percentage has changed over the years as the price of copper has fluctuated.

You can get some further ideas as to the range of possibilities by looking at the ten examples given in the TSM. However remember that these are not genuine investigations as the first ones were not submitted for assessment until the May 2016 session. For some genuine examples of IA reports that were submitted for the May 2017 session see Examples of teacher-marked IA reports and A genuine example of a moderated IA report.

All materials on this website are for the exclusive use of teachers and students at subscribing schools for the period of their subscription. Any unauthorised copying or posting of materials on other websites is an infringement of our copyright and could result in your account being blocked and legal action being taken against you.