CBA1 

The Extended Experimental Investigation. 

priorities for learning and teaching investigating and communicating in science, while at the same time developing their knowledge and understanding of science,

A student will, over a three-week period,

• formulate a scientific hypothesis, 

• plan an experimental investigation to test their hypothesis, 

• conduct an experimental investigation to test their hypothesis, 

• generate primary data, 

• analyse primary data, 

• reflect on the process, 

with support/guidance from the teacher.

Groupwork is permitted, but the report must be a body of work created by an individual.

The Extended Experimental Investigation comprises of four areas of activity:

1. questioning and predicting, 

2. planning and conducting,

3. processing and analysing, 

4. reflecting and reporting

Independent Variable

The part of the experiment YOU change, YOU control! What can you do to change the experiment.

This factor must be measurable, and by measurable, we mean being able to put a value on a quantity. 

Dependent Variable

The part of the experiment or the measurement that changes BECAUSE you changed something! the bit you measured after !

Measurable quantities: 

temperature // time// carbon dioxide production // density.  

Quantities of Heat are not usually measured, but found from other quantities, temperature in this case, therefore they are not measurable quantities.

We changed the _______ we used in each experiment.

That caused the _________ to change.

Controls / fixed variables

These are the factors (things) what you have kept the same in every run of the experiment, there will usually be many controls, not just one, many things that if they were changed would lead to change in the results. 

To keep these the same is to ensure a fair test. 

Only if the experiment was repeated and results averaged would certain parameters need to be replicated i.e. controlled. These would include: 

concentration of glucose, concentration and source of yeast, initial temperature etc.

In every run of the investigation we kept the ________ the same