1. Scientific & Chemical Foundations
The Scientific Method
Matter : Classification & Properties
Mathematics / Arithmetic:
Exponents, Significant Figures
Measurement & Units: (SI & metric)
Conversions and Relationships: Density, Percent
VOCABULARY: Key Terms
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3. Steps in the Scientific Method
1. Observations
- quantitative
- qualitative
2. Formulating hypotheses
- possible explanation for the observation
3. Performing experiments
- gathering new information to decide
whether the hypothesis is valid

4. Properties & States of Matter
Physical vs. Chemical Properties
Solid (s), Liquid (l), Gas (g)
Homogeneous vs. Heterogeneous Mixtures
Organization of atoms/molecules:
atoms/elements -> molecules/compounds
Extensive vs. Intensive Properties
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5. Organization of Matter

6. States of Matter

8. Physical & Chemical Properties

10. Types of Mixtures
Mixtures have variable composition of two or more components.
A homogeneous mixture is a solution (for example, vinegar: water + acetic acid, or steel & bronze: solid metals)
A heterogeneous mixture is, to the naked eye, clearly not uniform (for example, a bottle of ranch dressing with two layers: water + oil, or two solids: iron and sulfur)

11. Compounds & Elements
Compound: A substance with a constant composition that can be broken down into elements only by chemical processes,eg. FeS, Iron (II) sulfide
Element: A substance that cannot be broken into simpler substances by chemical means, eg. Fe, Iron or S8 Sulfur

12. Measurement & Units Qualitative vs. Quantitative
MASS (Chem: gram; SI: kg)
LENGTH (Chem: cm & others; SI: m)
TEMPERATURE (Celsius & Kelvin; SI: K)
VOLUME (Chem: mL; SI: Liter)
CHEMICAL AMOUNT: Mole (mol)
(Common Units in General Chemistry)
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13. Nature of Measurement
Measurement - quantitative observation consisting of 2 parts
Part 1 - number
Part 2 - scale (unit)
Examples:
20 grams
6.63   Joule seconds

14. Units of Measure

15. Powers of Ten: Exponents
Scale: Macroscopic vs. Microscopic
Video:
Language can describe scale (prefixes)
Relationship to Scientific Notation

16. Shorthand Prefixes

17. Mass and Volume Measurement

18. Liquid Measurement Tools

20. Volume

21. Temperature Scales Relative to Water

22. Temperature

23. Precision & Accuracy

24. Numbers Numeric expression is relative to the method of measurement.
How many numbers to include? Consider: Quantitative (exactness) vs. Qualitative
Short Hand expression: Scientific Notation
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25. Significant Figures
Nonzero integers always count as significant figures.
3456 has
4 sig figs.
In scientific notation?

26. Significant Figures
Exact numbers (conversion factors) can have an infinite number of significant figures.
1 liter = 1,000. ml, exactly
1 inch = cm, exactly

27. Zeros - Leading zeros do not count as significant figures. 0.0486 has
3 sig figs.
Number expressed in scientific notation?

28. Zeros Captive zeros always count as significant figures. 16.07 has
4 sig figs.
Number expressed in scientific notation?

29. Zeros Trailing zeros are significant only
if the number contains a decimal point.
9.300 has
4 sig figs.
Number expressed in scientific notation?

30. Mathematics & Arithmetic
Addition/Subtraction......
Multiplication/Division.....
What is “significant”?.....Rounding Off
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31. Computational Rules
Addition/Subtraction: Answer expressed to the least number of decimal places of the figures in the process
Multiplication/Division: Answer expressed to the least number of significant figures
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32. Conversion Factor Method (Dimensional Analysis)
Use numbers and “scale factor” UNITS
A Bookkeeping Method: Example
___ ft___in > ? m
(1 ft = 12 in; 2.54 cm = 1 in; 100 cm = 1 m)
___ft x 12 in/ft + ___in = ___in
___in x 2.54 cm/in x 1 m/100cm = ___m
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33. Density Density = Mass / Volume Units = g/mL or g/cm3; g/L
Least dense man made solid substance: Aerogel, D = x 10-3 g/cm3
Dair = 1.22 x 10-3 g/cm3 (1.22 g/L)
Densest known substance: white dwarf
1 teaspoon = 3.0 T; D = ? g/cm3 (1 tsp = 14.8 mL; 1 mL = 1 cm3 )
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34. Percent A comparison based on normalization to 100.
George Washington University: 64 unsealed addressed envelopes with $10 in each were dropped on campus in different classrooms.
In economics 18 of 32 were mailed, in business, history and psychology 10 of 32 were mailed. What is the percent for each of the 2 groups of students?
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35. Percent Continued
The Professor conducting the study received 43.75% of the $640 in the mail. How much did he receive?
How many of you would mail the envelop presuming no one knows you found it?
One student mailed an empty envelop with the return address: Mr. IOU, 1013 Indebted Lane, Bankrupt City, MS (WSJ 1/18/95)
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