1. Yesterday, we asked “are all chemicals bad?”  No, but some can be dangerous  Chemicals are everywhere  Which brings us to…

2. What is Chemistry?  the study of matter and the changes that it undergoes. What is Matter?  anything that has mass and takes up space What is Mass?  a measurement of the amount of matter in an object

3. Mass verses Weight  They are related, but what’s the difference?  Mass is universal, weight depends on gravity  Weight = mass times the gravitational pull

4. Branches of Chemistry  Organic  Inorganic  Analytical  Physical  Biochemical

5. Organic AAAArea of Emphasis Most carbon-containing chemicals EEEExamples: Pharmaceuticals Plastics

6. Inorganic AAAArea of Emphasis In general, matter that does not contain carbon EEEExamples: Minerals Metals and nonmetals Semi-conductors

7. Analytical AAAArea of Emphasis Components and composition of substances EEEExamples: Food Nutrients Quality Control

8. Physical AAAArea of Emphasis The behavior and changes of matter and the related energy changes EEEExamples: Reaction Rates Reaction Mechanisms

9. Biochemical AAAArea of Emphasis Matter and processes of living organisms EEEExamples: Metabolism Fermentation

10. Next, the Scientific Method

11. Why do we have the scientific method? Gives us logical steps to follow to assist us in answering a question.

12. What are the “steps”?  Develop a question  Conduct background research  Form a hypothesis  Test with an experiment  Make observations and collect data  Analyze the results  Draw conclusions  Report results and test again

13. Parts of an experiment

14. Independent Variable  P  Part of the experiment that the scientist changes   What is being tested   There is only one independent variable at a time.   What I change

15. Dependent Variable P Part of the experiment that changes because of the independent variable

16. Control P Part of the experiment that does not receive the independent variable

17. Constants P Part of the experiment that remain the same for every part of the experiment

18. Types of Data  Quantitative Data that is numerical in nature Data that is numerical in nature  Qualitative Data that is descriptive in nature Data that is descriptive in nature

19. An example experiment  A person wants to test whether music can help make plants grow. The person plants several seeds from the same batch into identical flower pots with identical potting soil, watering schedule and light supply. One flower pot is isolated from the sound supply, while the other pots are subjected to various types of music. After 1 month, the “healthiness” of each plant is measured.