Scientific Method

Science is the quantitative study of nature and the natural laws.

The name "science" comes from the Latin word "Scientia" which means knowledge.

There are two types of scientific studies:

Basic - long term, no short term practical objectives

Applied - short term, application oriented

In industry I worked as a polymer chemist developing coatings for the automotive industry and for paper coatings in containers. This work is very applied.

In my doctoral research and most of academic research, my emphasis has been on trying to understand molecular structure using quantum mechanics and statistical mechanics. When I was using these methods to try to develop a substitute compound for morphine, this work was applied. When I was trying to develop models for understanding how membranes function, the work was applied (using the models to predict activity) and basic (developing new models).

The scientific method forms the basis for how we interact with our environment. It is really rather intuitive as we can see by the following example.

Observation We make an observation (you have water in one kind of container and ethanol in another kind of container and observe that water boils at a higher temperature than ethanol)
Hypothesis1 We make an hypothesis about the observation (try to understand why the observation -- the different containers affected the outcome)
Theory1 We test our hypothesis (put them both in the same kind of container and repeat the observation).
We see that our hypothesis was wrong so we start the process over with another hypothesis. Reason a little: Since the containers are the same kind then the reason for the difference in boiling points must be in the liquids themselves.
H2 There are impurities within the liquids which cause the difference in boiling points.
T2 We purify each and measure the boiling points again and we see the same difference. Therefore H2 is also wrong so we reason again.
Reason some more: Well first we must know what boiling is. Boiling is putting heat into a liquid molecular system so that the molecules can go into the vapor state. Now it must get a little more complex for we have to know something about the structures of the molecules and the interactions between the molecules. We will come back to this problem as we learn more during the course, but I hope that this example helps to clarify the scientific method.

A law is a summary of observed fundamental natural behavior such as the observation that the total mass of material is not affected by a chemical change in those materials: Law of Conservation of Mass. A theory is a model which attempts to explain why something happens

We will come back to this boiling point problem as we learn more during the course, but I hope that this example helps to clarify the scientific method. You should use the scientific method in your analysis of everything, including the daily news to see if conclusions reached by the writers are valid. The following flow chart demonstrates the process.

Phase One Observation -->Hypothesis --> Experiment

Does the experimental data confirm the hypothesis?

No --> Back to Observation

Yes --> The hypothesis becomes a model (theory) with which we can work, but always remembering that further data may invalidate the model.

The model is subjected to further cycles in which we make predictions based upon our model but which were not included in the development of the model:

Phase Two Model --> Prediction --> Experiment

Does the model need to be discarded and we go back to phase 1?

------Yes, then we discard the model and not try to keep a bad model.

------No, then we modify the theory based upon the new experimental observations but without changing the basic tenants of the model.

Now take a practice quiz to help you understand if you understand the basic concepts.

You must use your real name when it asks for a name.

The test will only submit when you have answers all of the questions correctly.

If you are not taking this course for credit please do not answer all the questions correctly for I don't want to be flooded with email answers to the tests.