People to Know. Bring to Lecture Everyday: Course Materials. Bring to Discussion Everyday: Breakdown. Welcome to CHEM 102B. Coursework and Grading

Transcription

1 People to Know Welcome to CHEM 102B January 17, 2006 Timothy A. Richmond, Ph. D. Instructor Josh Ritchey Teaching Assistant Danielle Busser Teaching Assistant Lee Cremar Teaching Assistant Oscar Rodriguez, Jr. Teaching Assistant Course Materials Required: Chemistry 7th Edition, by Steven S. Zumdahl Scientific Calculator Handouts for Chemistry 102 Spring 2007 Interactive Course Guide Optional: A Partial Solutions Guide for Chemistry 7th edition Chemistry 102: Past Hourly Examinations, Fall Spring 2006 Bring to Lecture Everyday: Your Notes Handouts booklet Interactive Course Guide Calculator Bring to Discussion Everyday: Zumdahl Textbook Your Notes Handouts booklet Syllabus Calculator Breakdown Coursework and Grading Total = 800 points Hour Exams (3 hour exams) 300 points Quizzes (6) points Textbook Homework 30 points Online Homework 70 points Final Exam 300 points

2 Hour Exams (300 pts) Three 70 minute exams (100 points each) Hour Exam I: Tuesday, Feb 13, 7pm Hour Exam II: Tuesday, March 13, 7pm Hour Exam III: Tuesday, April 24, 7pm Quizzes (100 pts) 6 quizzes throughout the semester Total quiz score will be scaled to 100 points Any missed quiz will be a zero No Make-up quizzes Any excused quiz will have the average of all your other quizzes applied for that grade. Final Exam: Saturday May 5, 8-11am Conflict exams are available with advanced signup and id. Online Homework LON-CAPA (70pts) Weekly Homework Assignments Deadlines are Tuesdays at noon! Discussion Board available for each question LON-CAPA website or Textbook Homework Based upon completion of textbook problems assigned in syllabus Even numbered problems will be checked for completion not correctness Turned in on quiz days 5 points if all problems attempted Final Exam (300 points) Grades Saturday, May 5th, 8-11am Cumulative Review sessions will be held Grade A A- B+ B B- C+ C C- D+ D D- F Percentage of Points % % % % % % % % % % % 59.9% or lower

3 Excused Absence Policy Only university excused absences will be allowed Excused: Family emergency, documented illness, University sanctioned event Unexcused: vacation, great tickets to a Madonna concert, World Cup tickets, Cubs tickets, my computer died the night before the assignment was due, undocumented illness, overslept, etc Notify me or your TA as soon as possible Resources Course Website Chem Learning Center 212 Chem Annex Tutors Available 9-5pm Mon-Fri Office Hours Individual TA Office Hours My Office Hours 2-4 pm M/W in 2 Chem Annex University Educational Resources Textbook and Supplemental Texts Fellow Students Accommodations Meetings by appointment will be granted if the office hours are not convenient. If you require special accommodations please contact me as soon as possible so I can make appropriate arrangements. You will need university approved forms in order to be given accommodations Chemistry study of matter (Page 2) Matter = anything occupying space and having mass (Solid, Liquid, and Gas) Matter is made up of atoms Atoms = neutrons + protons + electrons Elements = collection of atoms of the same type (i.e. number of protons and electrons) Compounds = combine two or more different elements through chemical bonds Mixture = combination of two or more elements or compounds Mixtures (Page 3) Homogenous Mixture composition is the same throughout, there are no visibly distinguishable parts Heterogeneous Mixture composition is not uniform, there are visible distinguishable parts Mixtures can be separated by physical changes (such as boiling, melting, filtering) Compounds can be broken down into their individual elements by chemical change (making and breaking chemical bonds The Scientific Method (Page 4) Chemists are inquisitive people by nature. We watch, guess, check... repeat. 1. Make Observation 2. Formulate Hypothesis 3. Perform Experiment

4 Theories and Laws Observation does not explain why. Theory interpretation explaining why we observe what we do. Theories are educated guesses which are continually refined. Natural Law a generally observed and measurable behavior. Natural Laws summarize what is happening. Uncertainty in Measurements (Page 5) Precision closeness of measurements to each other, can you reproduce this measurement? Accuracy closeness of measurement to accepted value closeness of the average of a set of values to the true value Errors that cause uncertainty Random/Indeterminate Constant/Determinate Scientific Uncertainty The more digits, the less the relative uncertainty and the more precise the measurement The numbers reported in a measurement are limited by the measuring tool Significant figures in a measurement include the known digits plus one estimated digit Not significant -cosmetic purposes only Zeros that are Significant Not significant - placeholder Significant captive zeros Significant trailing zeros How many significant figures? 7 Significant Zeros? Significant captive zeros Not significant placeholders How many significant figures? 6 Mathematical Operations Uncertainty in the final calculation can never be better than the uncertainty of the numbers used in the calculation. x and number with fewest sig figs limits sig figs in answer 18 x = = and - answer has same number of decimal places as the number with fewest decimal places

5 Counting Significant Figures Number of Significant Figures? Scientific Notation Simplified way of writing numbers a) 12.3 ft b) seconds c) lbs d) 2,000 kg e) Watts f) = g) 3.2 x 16.5 = h) 1 dozen x 41.6 = 5,800,000 atoms becomes 5.8 x10 6 atoms 2 sig figs becomes x sig figs Making Measurements Quantitative Measurements have numbers 5 apples, 16 ounces, 34.3 fish Scientists use the SI system to define units Type of Measurement Mass Volume Length Temperature Basic Unit Grams Liters Meters Kelvin or Celsius (0 C is 273K) Memorize Table 1.1 (first 6) and Table 1.2 (in blue) on page 9 Prefixes Scientists add prefixes to show scale Increase or decrease basic unit by 10 Form new units larger or smaller than the basic units Indicate a numerical value prefix=value 1 kilometer=1000 meters 1 kilogram=1000 grams Some Metric-American Equalities 1 in.=2.54 cm 1 qt=946 ml 1 L=1.06 qt 1 lb = 454 g 1 kg=2.20 lb These equalities will be given to you during exams. Learning Check Select the unit you would use to measure A. Your height 1) millimeters 2) meters 3) kilometers B. Your mass 1) milligrams 2) grams 3) kilograms C. The distance between two cities 1) millimeters 2) meters 3) kilometers D. The width of an artery 1) millimeters 2) meters 3) kilometers

6 Conversion Factors Fractions in which the numerator and denominator are quantities expressed in an equality between those units Example 1 in. = 2.54 cm Factors: 1 in. and 2.54 cm 2.54 cm 1 in. Dimensional Analysis Using units to solve the problem Ex: You pass a road sign saying New York 112 km If you drive at a constant speak of 65mi/ h, how long should it take you to get to New York? mi 1hr 112km = 1.1hr = 1hr6min 1km 65mi If your car gets 28 miles to the gallon, how many liters of gasoline are necessary to travel 112 km? mi 1gal 3.785L 112 km = 9. 4L 1km 28mi 1gal Note: 1 km = miles 1 gal = L