Welcome to AP Chemistry

1. Welcome to AP Chemistry

2. What is AP Chemistry? • It is several things • Equivalent of 1 year college inorganic chemistry class • A class that will prepare you for a test • May 17 • Hard work • A wonderful way to start the day • Now on to the details

3. Rules and Procedures • You know the basic rules but here are a few that are specific for this class • No food drink or gum • LATE WORK • If you forget to bring in your homework, I will accept it ONE day late with a parent's signature, for full credit. • I will not accepted it any later.

4. Rules and Procedures • MAKE-UP WORK • It is your responsibility to make up all the work you missed. You have the same number of days that you were absent to turn in the missing work. • Pick up any missing work, and notes before or after class. • If you miss a test or quiz, it must be made up outside class.

5. Rules and Procedures • TARDIES • You will be allowed one ”free" tardy per semester. • The second and every subsequent tardy will result in a detention. • Repeated tardies will result in parent contacts, and referrals, AND MAY RESULT IN BEING DROPPED FROM THE CLASS.

6. Rules and Procedures • PASSES • Since every minute of class time is valuable, hall passes will be given only on an emergency basis, with a limit of one per semester, except under special circumstances.

7. Rules and Procedures • LAB- Because of the importance of safety in the lab, violation of laboratory safety rules and procedures may result in loss of lab privileges.

8. Grading • Percentage scale 94-100% A 70-75% C 90-94% A- 65-70% C- 87-90% B+ 62-65% D+ 84-87% B 58-62% D 80-84% B- 55-58% D- 75-80% C+ 0-54% F

9. Grading • Quarter Grade • Tests 50% • Homework/Classwork 20% • Quizzes 15% • Lab Reports 15% • Semester Grade • 40% from each quarter • 20% on final

10. Extra Credit!! • Assignments will be provided approximately mid- quarter. • They may be turned in any time until the due date,(during the last week of the quarter) • Extra credit may be used to raise the quarter grade by up to one letter grade. • Extra credit is meant to be extra, so it will not be accepted if more than 10% of the other assignments are not turned in.

11. What you need for class • Paper • Pencil or pen, • Calculator- scientific • Book? • Not unless I let you know • Lab Notebook

12. Internet Ready • http://mrgreen.tierranet.com • My email is tvgreen@aol.com

13. Why First Period? • College chemistry labs take more than 56 minutes, • To do those labs we will have to come early • I will give you notice of when

14. Any questions? • Lets get started

15. Significant figures • Meaningful digits in a MEASUREMENT • Exact numbers are counted, have unlimited significant figures • If it is measured or estimated, it has sig figs. • If not it is exact. • All numbers except zero are significant. • Some zeros are, some aren’t

16. Which zeroes count? • In between other sig figs does • Before the first number doesn’t • After the last number counts iff • it is after the decimal point • the decimal point is written in • 3200 2 sig figs • 3200.4 sig figs

17. Doing the math • Multiplication and division, same number of sig figs in answer as the least in the problem • Addition and subtraction, same number of decimal places in answer as least in problem.

18. More Preliminaries Scientific Method Metric System Uncertainty

19. Scientific method. • A way of solving problems • Observation- what is seen or measured • Hypothesis- educated guess of why things behave the way they do. (possible explanation) • Experiment- designed to test hypothesis • leads to new observations, • and the cycle goes on

20. Scientific method. • After many cycles, a broad, generalizable explanation is developed for why things behave the way they do • Theory • Also regular patterns of how things behave the same in different systems emerges • Law • Laws are summaries of observations

21. Scientific method. • Theories have predictive value. • The true test of a theory is if it can predict new behaviors. • If the prediction is wrong, the theory must be changed. • Theory- why • Law - how

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

23. Metric System • Every measurement has two parts • Number • Scale (unit) • SI system (le Systeme International) based on the metric system • Prefix + base unit • Prefix tells you the power of 10 to multiply by - decimal system -easy conversions

24. Metric System • Base Units • Mass - kilogram (kg) • Length- meter (m) • Time - second (s) • Temperature- Kelvin (K) • Electric current- ampere (amp, A) • Amount of substance- mole (mol)

25. Prefixes • giga- G 1,000,000,000 109 • mega - M 1,000,000 106 • kilo - k 1,000 103 • deci- d 0.1 10-1 • centi- c 0.01 10-2 • milli- m 0.001 10-3 • micro- m 0.000001 10-6 • nano- n 0.000000001 10-9

26. Deriving the Liter • Liter is defined as the volume of 1 dm3 • gram is the mass of 1 cm3

27. Mass and Weight • Mass is measure of resistance to change in motion • Weight is force of gravity. • Sometimes used interchangeably • Mass can’t change, weight can

28. Uncertainty • Basis for significant figures • All measurements are uncertain to some degree • Precision- how repeatable • Accuracy- how correct - closeness to true value. • Random error - equal chance of being high or low- addressed by averaging measurements - expected

29. Uncertainty • Systematic error- same direction each time • Want to avoid this • Better precision implies better accuracy • you can have precision without accuracy • You can’t have accuracy without precision

30. Dimensional Analysis Using the units to solve problems

31. Dimensional Analysis • Use conversion factors to change the units • Conversion factors = 1 • 1 foot = 12 inches (equivalence statement) • 12 in =1= 1 ft. 1 ft. 12 in • 2 conversion factors • multiply by the one that will give you the correct units in your answer.

32. Examples • 11 yards = 2 rod • 40 rods = 1 furlong • 8 furlongs = 1 mile • The Kentucky Derby race is 1.25 miles. How long is the race in rods, furlongs, meters, and kilometers? • A marathon race is 26 miles, 385 yards. What is this distance in rods, furlongs, meters, and kilometers?

33. Examples • Science fiction often uses nautical analogies to describe space travel. If the starship U.S.S. Enterprise is traveling at warp factor 1.71, what is its speed in knots? • Warp 1.71 = 5.00 times the speed of light • speed of light = 3.00 x 108 m/s • 1 knot = 2000 yd/h exactly

34. Examples • Apothecaries (druggists) use the following set of measures in the English system: • 20 grains ap = 1 scruple (exact) • 3 scruples = 1 dram ap (exact) • 8 dram ap = 1 oz. ap (exact) • 1 dram ap = 3.888 g • 1 oz. ap = ? oz. troy • What is the mass of 1 scruple in grams?

35. Examples • The speed of light is 3.00 x 108 m/s. How far will a beam of light travel in 1.00 ns?

36. Temperature and Density

37. Temperature • A measure of the average kinetic energy • Different temperature scales, all are talking about the same height of mercury. • Derive a equation for converting ºF toºC

38. 0ºC = 32ºF 32ºF 0ºC

39. 100ºC = 212ºF 0ºC = 32ºF 0ºC 100ºC 212ºF 32ºF

40. 100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 0ºC 100ºC 212ºF 32ºF

41. 100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 1ºC = (180/100)ºF 1ºC = 9/5ºF 0ºC 100ºC 212ºF 32ºF

42. ºF ºC

43. (0,32)= (C1,F1) ºF ºC

44. (0,32) = (C1,F1) (120,212) = (C2,F2) ºF ºC

45. Density • Ratio of mass to volume • D = m/V • Useful for identifying a compound • Useful for predicting weight • An intrinsic property- does not depend on what the material is

46. Density Problem • An empty container weighs 121.3 g. Filled with carbon tetrachloride (density 1.53 g/cm3 ) the container weighs 283.2 g. What is the volume of the container?

47. Density Problem • A 55.0 gal drum weighs 75.0 lbs. when empty. What will the total mass be when filled with ethanol? density 0.789 g/cm3 1 gal = 3.78 L 1 lb = 454 g