8 September 2011

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8 September 2011. Objective : You will be able to: collect and analyze data to determine the thickness of aluminum foil. demonstrate mastery of course expectations. Do now : Pick up a syllabus. Do now starts Monday. Agenda. Do Now Collect data for Al foil lab - PowerPoint PPT Presentation

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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 NowII. Collect data for Al foil labIII. Aggregate class data and Dixon’s Q testIV. Discussion of significant figuresV. Course syllabus and expectationsVI. 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, we’ll look for outliers.

Dixon’s Q Test for Outliers

x2 = closest value to suspectedx1 = suspected outlierxN-x1 = range of values

Qexp x2 x1

xN x1

Table of Critical Values

Discard if Qexp > Qcrit

Expectations

Email: kboiteau@prospecthillacademy.org

Website: www.phascience.wordpress.com (for assignment sheets, some problem set answers, etc.)

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:Quantity Name Symbo

lLength meter mMass gram gTime second stemperature kelvin Kamount of substance

mole mol

Prefixes: the important onesPrefix Symbo

lMeaning

kilo k 1000 (103)centi c 1/100 (10-2)milli m 1/1000 (10-3)micro μ 1/100,000,000

(10-6)nano (for wavelength)

n 1/100,000,000,000 (10-9)

Converting between orders of magnitude

Example 1: Express 3000. mL in liters.

Example 2: Express 0.0040 grams in milligrams.

Volume

Vmd

1 mL=1 cm3

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=oC + 273 0 K is the temperature at which… Don’t 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: 0.000 000 000 000 000 000 000 001 66 g

c. 0.0005 secondsd. 4,000,000 gramse. 4.32x103 mLf. 9.32x10-5 cm3

g. 6.02x1023 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 350,246.2544330 cubic feet per year.

What’s 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)345597.2145.456

B. Zeros Leading zeros that come before all

the nonzero digits do NOT count as significant figures

Ex: 0.0025 has two sig. fig. The zeros are “leading” and do not count.0.230.00040.03564

Captive zeros are between nonzero digits and DO count as sig. fig.

Ex: 1.008 has four sig. fig. The zeros are captive and DO count.10,0041.0000061,000,000,000,000,567

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.

1.000000 3,000,000 3.00000 30.00 300 300.

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 people100 baseballs

Significant Figures

a. 5 cmb. 500 cmc. 5.0 gd. 5.000 mge. 500. Kf. 5.000x1010 atomsg. 505 desksh. 505,00.050 L

Addition/Subtraction Rules

Use the fewest number of digits to the right of the decimal place in the original numbers. Ex. 89.332 + 1.1 = 90.432 Round to

Multiplication/Division Rules

Round to the fewest number of significant figures present in the original numbers Ex: 2.8 x 4.5039 = 12.61092

Round to… Ex: 6.85/112.04 = 0.0611388789

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 3.4x103 liters?

Homework

Check the answers to your chapter 1 summer assignment at

www.phascience.wordpress.com 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. = 453.6 g 1 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 34.90 grams, and the full vase is 55.85 grams. The density of water is 0.9976 g/cm3. Calculate the volume of the vase in cm3.

Agenda

I. Homework quizII. Difficult volume conversion problemIII. 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 m3?

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.