1. Introduction to Chemistry Dr. Richard Malik
Chapter 1
Introduction to Chemistry
Dr. Richard Malik

2. The Stories of Two Chemicals
Ozone is formed when oxygen gas is exposed to ultraviolet radiation in the stratosphere forming an ozone layer.
Ultraviolet radiation (UV) is harmful to plants and animals.
Importance of the Ozone Layer:
Ozone absorbs most of the harmful UV radiation before it reaches Earth’s surface.

3. The Stories of Two Chemicals
Chlorofluorocarbons (CFC)
Used as coolant for refrigerators
Used as propellants in spray cans
CFC’s escape into the atmosphere causing a thinning of the ozone layer.

4. What is Chemistry?
Chemistry is the study of the matter, its composition, properties, and the changes it undergoes.
Applied chemistry is the using of chemistry to attain certain goals, in fields like medicine, agriculture, and manufacturing
Pure chemistry gathers knowledge for knowledge’s sake

5. Which Comes First? Pure Chemistry Applied Chemistry
Usually comes first, applied later
Called technology
Or engineering
Pure chemistry can explain behavior that has been used without knowing why
Steel swords
Can’t be good or bad
Can be good or bad depending on use

6. Mass and Matter?
Matter is anything that has mass and takes up space. (Ex. Book)
Mass is the amount of matter in an object. Measured in grams (g)
Weight- The weight of an object is a measure of the force of gravity on the object.
Your weight will change if you move from the North pole to the equator but our mass will stay the same.

7. Branches of Chemistry
Analytical Chemistry -studies composition of substances.
Organic Chemistry -compounds containing carbon
Inorganic Chemistry -substances without carbon
Biochemistry- Chemistry of living things
Physical Chemistry studies behavior of substances
rates and mechanisms of reactions
energy transfers

8. Applied Chemistry Material Design Plastics Paints Nanotechnology Scale
Macroscopic- Big enough to see
Microscopic- Too small to see unaided
Nanotechnology- manipulating individual atoms and molecules

9. Applied Chemistry Agriculture Production- fertilizers, soil tests
Protection – pesticide, herbicide
Medicine
Drugs
Materials- hips, artificial skin
Biotechnology- using organisms as a means of production

10. Scientific Method A way of solving problems or answering questions.
Step 1:Observation- the act of gathering information. Observations can be:
Qualitative data- Anything that relates to the five senses. (look, feel, sound, taste, smell)
Quantitative data- Numerical information that tells you how much, how little, etc.

11. Scientific Method (cont.)
Step 2:Hypothesis- a testable statement or prediction that explains the cause of the observation, based on research and previous knowledge
Step 3: Experiment- a process designed to test the hypothesis.
only two possible answers, hypothesis is right or wrong
Generates data -observations from experiments.

12. Scientific Method (cont.)
Step 4 Conclusion: A judgment based on the information obtained. Can lead to a theory.
Theory - Hypothesis supported by many experiments.
Scientific Law- Summary of accepted facts of nature.
Step 5 Modify hypothesis - repeat the cycle.

13. Cycle repeats many times.
By you and by others
The hypothesis gets more and more certain.
Becomes a theory
A thoroughly tested model that explains why things behave a certain way.
Observations
Hypothesis
Experiment

14. Theory can never be proven.
It is the best explanation
Useful because they predict behavior
Help us form mental pictures of processes (models)
Observations
Hypothesis
Experiment

15. Another outcome is that certain behavior is repeated many times
Scientific Law is developed
Description of how things behave
Usually an equation
Law - how
Theory- why
Observations
Hypothesis
Experiment

16. Law Modify Observations Theory (Model) Hypothesis Experiment
Prediction
Modify
Experiment
Law
Experiment

17. Variables
Controlled experiment- Only want one thing to change at a time in a laboratory.
Independent variable- What you change or control directly.
Dependent variable – What changes as a result of changing the independent variable. No direct control.

18. References
Dingranso, L, Gregg, K, Hainen, N, & Wistrom, C (2002). Chemistry: matter and change. Columbus, OH: Glencoe/McGraw-Hill.
Green, N.D., Mr. Green’s Home Page. Retrieved October 17, 2008 from