Variables are the factors that may change or affect the results of an experiment. In order to carry out an investigation accurately you must make sure you are performing a fair test. This means that you must control the variables of the experiment.  There are three different variables that need to be considered:

1. Independent variable  - this is the variable that you manipulate or change on purpose each time. 

2. Dependent variable - this is the variable that you measure each time and it's reading is the result of the change on the independent variable.  

3. Controlled variables - these are all the things that were kept the same in the experiment, remaining unchanged and constant

This is the list of materials or items you are using during the practical, include quantities (glassware, chemicals, tools, etc.) To write a good material list you need to ensure there are clear measurements of quantities or sizes of equipment of substance. 

The steps needed to perform or conduct the experiment.  This is written in paragraph form, using third person and past tense. A method/procedure must   include:

• Detailed directions on each step

• The number of times the procedure needs to be repeated

• How to record the data

• Units of measurement that are explicit

Presented in tables or graphs, observations are included, calculations may also be included in this section

In the discussion you provide answers to the experimental question using evidence from your tables and graphs.  You talk about what trends you notice from the data, explain any anomalies or outliers and why they may have happened. It is also important to suggest ways to improve the experiment if conducted again. 

A summary of the experiment and what was found that usually reflects back to the aim of the experiment. Your conclusion should answer your aim and hypothesis. Your conclusion should be based solely on your results.