Unit 1 Intro to Chemistry and Measurement

1. Unit 1Intro to Chemistry and Measurement Intro to Chemistry and Physics Mr. Patel SWHS

2. Topic Outline • Learn Major Elements and Symbols • Intro to Chemistry (1.1, 1.2) • Significant Figures (3.1) • Measurement (3.1, 3.2) • Factor-Label Method of Conversions (3.3)

3. Intro to Chemistry • Matter – anything that has mass and occupies space • Chemistry – study of the composition of matter and the changes it undergoes

4. Intro to Chemistry • Chemistry affects all aspects of life and other natural events! • Food Digestion • Leaves changing colors • Muscle contraction • Driving cars

5. Intro to Chemistry • Five different areas or branches of chemistry

6. Organic Chemistry • Study of all chemicals containing carbon

7. Inorganic Chemistry • Study of chemicals that do not contain carbon

8. Biochemistry • Study of processes that occur in living things

9. Analytical Chemistry • Study that focuses on the composition of matter

10. Physical Chemistry • Area that deals with the rate, mechanism, and energy transfer of chemistry

11. Types of Research • Pure Chemistry – increase chemical knowledge • Applied Chemistry – goal oriented

12. History of Chemistry • Alchemy - change other metals to gold • Lavoisier – Father of Modern Chemistry • Observation to measurement

13. Scientific Method

14. Significant Figures • Sometimes we estimate numbers • If we measure between 9.8 and 9.9, we may say it is 9.85. • We know that the 9 and 8 are definite; 5 is estimated. • Discuss accuracy/precision later • Significant Figures – the digits from a measurement that are known precisely plus an estimated digit

15. Measurement • Measurement – quantity with a number and unit • Accuracy – how close you are to the true value • Precision – how close your measurements are to one another

17. Scientific Notation • Used for very large or very small numbers • Converts a single number to a product of two numbers • Ex: 8000  8 x 103 • Ex: 0.234  2.34 x 10-1

18. Scientific Notation Practice • 252 • 125000 • 0.00305 • 0.00000000548 • 2.52 x 102 • 1.25 x 105 • 3.05 x 10-3 • 5.48 x 10-9

19. International System of Units (SI) • Five SI base units: • meter (length) • kilogram (mass) • Kelvin (temperature) • Second (time) • Mole (amount)

20. Metric Conversions

21. Factor-Label Method • Write down starting and ending unit • Write all relevant conversion factors • Cancel units to get to end unit • To cancel a unit, the unit must be on the top and bottom

22. Conversion Examples

23. Presenting Data • Data – numbers obtained or observations made during the experiment • Organize data so that it is easier to read • Organize data with graphs and tables

24. Data Tables • Simplest way to organize data • Purpose: to show pure data. • Table has a Title, category titles, and units.

25. Bar Graph • Purpose: compare a set of measurements

26. Circle Graph • Purpose: to show parts out of a whole • Circle Graph has a title, axis labels, and bars that show data

27. Line Graphs • These lines are very important: slope • slope = Rise/Run • Proportional graphs • Inverse graphs • Always has Title, Axis Labels with units, any relationships.

29. Variables • Independent Variable – what is being changed by the researcher • Always along the x-axis of a graph (horizontal) • Time is usually always independent variable • This will cause something to happen

30. Variables • Dependent Variable – the factor that is changing because of what the researcher changed • Always along the y-axis on a graph (vertical) • This is the response to the independent variable

31. Correlation • Line Graphs can show a positive or negative correlation. • This is correlation NOT causation • We can not say one thing causes another • One thing may lead to another