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IB Chemistry Internal Assessment
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Design Identify identify a problem or research question.
Design a way to control the variables Design a method to measure the variables
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Aspect 1: Defining the roblem and selecting variables
State a problem or question clearly. Be specific when you do this. Refer to your experiment. The problem can be stated in the form of a hypothesis. Include relevant background information. Write the chemical equation for the reaction to be studied. Clearly state the relevant variables in the investigation.
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Variables What is the independent variable and how will it be changed?
What is the dependent variable and how will it be measured? List variables that need to be controlled (Kept the same) and state how they will be controlled.
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Aspect 2: controlling variables
List five variables that need to be controlled and state how they will be controlled.
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Aspect 3: developing a method for collection of data
The method should allow for the collection of sufficient relevant data to answer the research question. Sufficient data: Vary the independent variable five different times. Repeat each trial three times.
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Data collection and processing
Raw data is the actual data measured. This must include quantitative and qualitative data.
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Aspect 1: Data Collection
Raw data is the actual data measured. Put the raw data in a table. For Quantitative Data: (Measurements) The data table must have a title, labels and units. Uncertainties should always be included. Qualitative data: (Observations) must also be included
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Data Collection Masses of reactants and observations
Substance Mass added grams Observations Magnesium metal 24.01 Shiny metal Copper(II) nitrate 62.4 Green solid Blah blah…. What is good about this table? What is missing?
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Aspect 2: Processing Data
Combine and manipulate raw data to determine the value of a physical quantity (such as adding, subtracting, squaring, dividing) Take the average of several measurements Transform data into a form suitable for graphical representation.
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Aspect 3: Presenting processed data
When data is processed, the uncertainties associated with the data must also be considered. Decide upon a suitable presentation format themselves (for example, spreadsheet, table, graph, chart, flow diagram, and so on). There should be clear, unambiguous headings for calculations, tables or graphs.
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More Details Show the equation you are using for the calculation
Show ONE sample calculation Remember significant figures. Put all calculated results in a table with units.
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Conclusions and Evaluation
The results are discussed and reviewed, procedures are evaluated and conclusions are drawn. Demonstrate an ability to coherently discuss the broader significance of their findings.
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Aspect 1: Conclusions The conclusion must take into account any systematic or random errors and uncertainties. A percentage error should be compared with the total estimated random error as derived from the propagation of uncertainties. Compare the experimental value with the textbook or literature value. The literature consulted should be fully referenced.
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Aspect 2: Evaluating procedure(s) and suggesting improvements
The design and method of the investigation must be commented upon as well as the quality of the data. List the weaknesses and suggest how significant the weaknesses are. Include comments about the precision and accuracy of the measurements. Consider the processes, use of equipment and management of time.
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Aspect 3: Improvements Suggestions for improvement should be based on the weaknesses and limitations identified. Suggest modifications to the experimental techniques. The modifications should address issues of precision, accuracy and reproducibility of the results. Students should suggest how to reduce random error, remove systematic error and/or obtain greater control of variables. The modifications proposed should be realistic and clearly specified.
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Evaluation and Improvements worksheet
Error/Weakness Effect on the experiment improvements
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Manipulative Skills This criterion is assessed summatively once only at the end of the course.
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Aspect 1: Following instructions
Indications of manipulative ability are the amount of assistance required in assembling equipment, the orderliness of carrying out the procedure(s) and the ability to follow the instructions accurately. The adherence to safe working practices should be apparent in all aspects of practical activities.
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Aspect 2: carrying out techniques
A variety of techniques must be demonstrated Students should be able to use techniques well.
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Aspect 3: working safely
The student’s approach to safety during investigations in the laboratory or in the field must be assessed. This includes both safe conduct as well as safe use of equipment and substances.
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