1. Two distinct realms of scientific knowledge
The Scientific Method
Two distinct realms of scientific knowledge

2. Ppt00_Scientific Method
Goals
Compare and contrast the two fundamentally different kinds of scientific knowledge
Relate these two kinds of knowledge to the more conventional description of the “Scientific Method”
Ppt00_Scientific Method

3. The Scientific Approach to Knowledge (Section 1.2 in Tro)
Two “realms” in science:
“WHAT HAPPENS?”
vs “WHY DOES IT
BEHAVE THAT WAY?”
Description/Behavior
Explanation
Raw Data
Observations (5 senses)
Measurements (using a tool)
Model
Hypotheses / Postulates
(IF these are true, THEN behavior will be as observed)
Pattern? Generalizable?
Relationship between quantities
→ LAW
If after much evidence is found to support model,
→ THEORY
Conservation of Mass
Vgas = kTgas (Charles’ Law)
Atomic Th.
KMT

4. Ppt00_Scientific Method
Important!
Laws don’t “turn into” Theories!
They are fundamentally different kinds of info.
Laws describe
Theories explain
Both are important …
…and being able to distinguish description from explanation is also important!
Ppt00_Scientific Method

5. “Conventional Approach”, with Commentary From Handout Packet #1
From Atkins, P; Jones, L. (1997) Chemistry: Molecules, Matter, and Change

7. Tro’s Flow Diagram to Describe The Scientific Method (Fig. 1.2)
Ppt00_Scientific Method

8. Ppt00_Scientific Method
Example
Characterize each statement as best you can as either an observation, a law, a hypothesis, or a theory. Justify your answer.
When liquid water is heated sufficiently in a tea pot, bubbles form rapidly throughout the liquid and rise.
The composition of the bubbles is water.
The molecules in the bubbles are more spread out than the molecules in the liquid.
When any liquid is heated sufficiently, bubbles will eventually form (assuming it does not decompose).
Ppt00_Scientific Method

9. “Theory” often misused!
“Just a theory” is really an insult to scientists
To become a scientific “theory”, a model must “explain” all currently available data
But….theories cannot ever be “proven”
How can you ever know that there won’t come a time when a piece of data will be collected which is not consistent with the model (theory)?
Ppt00_Scientific Method

10. Ppt00_Scientific Method
(rest of article omitted)
Ppt00_Scientific Method

11. Laws/Patterns &Theories are a theme of this course!
Ppt00_Scientific Method

12. Ppt00_Scientific Method
(continued)
Ppt00_Scientific Method