How do Scientists Design Experiments Using the Scientific Method?
- As in all other fields of science, the knowledge of chemistry is gathered through the scientific method, a systematic method used by scientists in their investigations.
- Generally, the scientific method starts with careful observations on a situation. An inference is made based on the observations.
- An inference is a smart guess. To verify it, a hypothesis is formulated and tested through a carefully planned and controlled procedure called an experiment.
- Scientific attitudes and noble values should be inculcated in carrying out the experiments. For example:
(a) An experiment is planned and carried out systematically and diligently.
(b) All observations and collection of data must be done honestly and objectively.
(c) Interpretation of data, inferences and conclusions are made with rational, critical and analytical thinking.
Steps Involved in the Scientific Method
- Make observations using five senses.
- Make an inference based on the observations.
- Identify the problem based on the inference made.
- Make a hypothesis about the relationship between the manipulated variable and the responding variable.
- Identify the variables:
- Manipulated variable (the factor that is purposely changed in an experiment)
- Responding variable (the factor that changes with the manipulated variable)
- Controlled variable (the factors that are kept constant throughout an experiment)
- Control the variables: Decide how to manipulate the chosen variable, what to measure and how to keep the controlled variables constant.
- Plan an experiment: Determine the list of materials and apparatus, the procedure of the experiment, the method to collect data and the ways to analyse and interpret the collected data.
- Collect the data: Make observations or measurements and record them sistematically.
- Interpret the data: Organise and analyse data. Calculations, graphs or charts are usually drawn to look for any relationship between the variables.
- Make a conclusion: Make a statement about the outcome of the experiment and whether the hypothesis is accepted.
- Make a Report