8 September 2011 Objective: You will be able to: a. collect and analyze data to determine the thickness of aluminum foil. b. demonstrate mastery of course expectations. Do now: Pick up a syllabus. Do now starts Monday. Agenda I. Do Now II. Collect data for Al foil lab III. Aggregate class data and Dixons Q test IV. Discussion of significant figures V. Course syllabus and expectations VI. Unit 1 review Homework: Materials, signed syallabus, $10 Check Unit 1 summer assignment answers on the blog. Class Aggregate Data When you finish, enter your data into the spreadsheet. Then, well look for outliers. Dixons Q Test for Outliers x 2 = closest value to suspected x 1 = suspected outlier x N -x 1 = range of values Table of Critical Values Discard if Q exp > Q crit Expectations Website:(for assignment sheets, some problem set answers, etc.)www.phascience.wordpress.com Office hours: Tuesdays 3:30-4:30 pm and by appointment (before and after school) in Room 203 Office: Room 204 Materials Three ring binder and loose leaf paper Lab Notebook (available from Ms. Boiteau for $10) Scientific calculator Pens or Pencils Chemistry Textbook Chapter 1: Review You are responsible for non-problem- solving concepts outlined in your chapter 1 notes Measurement SI Units: QuantityNameSymbol Lengthmeterm Massgramg Timeseconds temperaturekelvinK amount of substancemolemol Prefixes: the important ones PrefixSymbolMeaning kilok1000 (10 3 ) centic1/100 (10 -2 ) millim1/1000 (10 -3 ) micro 1/100,000,000 (10 -6 ) nano (for wavelength) n1/100,000,000,000 (10 -9 ) Converting between orders of magnitude Example 1: Express mL in liters. Example 2: Express grams in milligrams. Volume 1 mL=1 cm 3 Example The density of mercury, the only metal that is liquid at room temperature, is 13.6 g/mL. Calculate the mass of 5.50 mL of the liquid. Temperature Scales K= o C 0 K is the temperature at which Dont say degrees Kelvin! Scientific Notation a. 602,200,000,000,000,000,000,000 hydrogen atoms in a gram of hydrogen b. Mass of one hydrogen atom: g a seconds b. 4,000,000 grams c. 4.32x10 3 mL d. 9.32x10 -5 cm 3 e. 6.02x10 23 atoms An engineer was responsible for calculating amount of water that overflowed from a dam. He measured all of the water runoff going into the reservoir (1.2 million cubic feet per year), the rainfall (860 cubic feet per year), and the capacity of the reservoir (3.8 million cubic feet). He did some fancy calculations. He reported to his boss that the overflow from the dam would be 350, cubic feet per year. Whats wrong here? Determining Number of Significant Figures A. Nonzero integers count as significant figures Ex. Any number that is NOT zero (1, 2, 3, 4, 5, 6, 7, 8, 9) B. Zeros Leading zeros that come before all the nonzero digits do NOT count as significant figures Ex: has two sig. fig. The zeros are leading and do not count Captive zeros are between nonzero digits and DO count as sig. fig. Ex: has four sig. fig. The zeros are captive and DO count. 10, ,000,000,000,000,567 Trailing zeros are to the right end of the number and DO count as sig. fig. if the number contains a decimal point. Ex.: 100 has only one sig. fig. because the trailing zeros DO NOT have a decimal point. Example: 1.00 has three sig. fig. because the trailing zeros DO have a decimal point ,000, C. Exact numbers Any number found by counting has an infinite number of significant figures. Ex: I have 3 apples. The 3 has an infinite number of significant figures. 50 people 100 baseballs Significant Figures a. 5 cm b. 500 cm c. 5.0 g d mg e K f x10 10 atoms g. 505 desks h. 505, L Addition/Subtraction Rules Use the fewest number of digits to the right of the decimal place in the original numbers. Ex = Round to Multiplication/Division Rules Round to the fewest number of significant figures present in the original numbers Ex: 2.8 x = Round to Ex: 6.85/ = Round to Exact Numbers Have infinite significant figures 12 people, 5 atoms, etc. 1 inch = 2.54 cm conversion factors are considered exact Expressing Numerical Answers EVERY TIME you write down a numerical answer in this class: a. Round it to the correct number of significant figures. b. Put it in scientific notation if at all possible. c. Include correct units. Dimensional Analysis How many seconds are there in 4.00 years? How many milliliters are equal to 3.4x10 3 liters? Homework Check the answers to your chapter 1 summer assignment at Come to class with questions!! Materials and $10 12 September 2011 Objective: You will be able to demonstrate the Do Now procedure review unit 1 objectives Do now: Label a piece of notebook paper Week of Sept. 12 Silently and on your own, with the use of your notes and homework, answer the following questions: Homework Quiz: 1. I am five and a half feet tall and weigh 140 lbs. Express my height in meters and my mass in kilograms. 1 lb. = g1 m = 3.28 feet 2. The following procedure was used to determine the volume of an irregularly-shaped vase: The vase was weighed dry, then filled with water. The mass of the empty vase is grams, and the full vase is grams. The density of water is g/cm 3. Calculate the volume of the vase in cm 3. Agenda I. Homework quiz II. Difficult volume conversion problem III. Ch 1 questions? IV. Ch 1 problem set Homework: Check chapter 2 summer assignment answers online Ch 1 AP problem set: Thurs. Announcements Period 0 some Special Wednesdays Nov. 23 Dec. 7 Jan 25 Mar 21 Apr 11 Be a TA! See Mr. Moretti! An average adult has 5.2 L of blood. What is the volume of blood in m 3 ? Questions about the Chapter 1 Homework? Chapter 1 problem set due Friday Homework Check chapter 2 summer assignment answers online Ch 1 AP problem set: Thurs.