“Do Now” for 9/21/09» You do not need your green “Do Now” sheet, get your lab

notebook.

•Complete creating your procedure for your group’s unknown sample in your lab notebooks. You need to get this initialed before you will get your unknown! •Check to make sure that you have the proper heading on all of the pages of your lab notebook that correspond to your lab.

• Experiment # is 02 • Title = “5 White Substances”• the date should match the date in which you are

conducting that particular part of the lab • Your name

• Your group members’ names

Announcements for 9/21/09

• Be sure you are handing in the yellow carbon copy of your labs.

• Today is the last day HW will be accepted w/out a 50% point reduction.

• Make sure the fringes are torn off the side of the papers: most are perforated so this should not be too difficult for you!– Make sure those fringes make it into the garbage!

• Quiz tomorrow in the first 10 min of class – be sure to study! You will need paper and something to write with!

For today:1. Work with your group towards identifying your

unknown substances (there will be 3 or 4!)– Document the results of every test you perform

• Make a data table similar to the one you have been using.

2. Write the letters of the substances you believe to be in your unknown with at least 1 sentence per substance explaining your reasoning.

3. Call your teacher over to check over your responses and supply you with the post-lab questions.

4. Staple and turn in the carbon copy to ALL pages associated with this lab into the HW Bin.

“Do Now” for 9/22/09 QUIZ!!

• You will need:– Blank sheet of paper– Something to write with (blue/black/pencil only)– Clear you desk

• We will begin when everyone is ready!

During the quiz:• Answer ?’s on a separate sheet of paper.• No talking, or you loose points.• Raise your hand if you have a question.• No notes.• Turn in quiz and answer sheet to the front, get ready to take notes!

What are the layers of the atmosphere?

9/__/09 Chapter 1What is the ozone layer?

•Absorbs ultraviolet (UV) light that can damage organisms.•Is formed from oxygen gas (O2) being exposed to UV radiation = forms O3

What’s going on with it?

•Thinning layer detected in 1980 over Antarctica•Link discovered between CFC concentration and ozone depletion.

Write this down!

Do Now - 9/23/09 – yes, on green sheet 1. Copy, “kilo-hecto-deca-unit-deci-centi-

milli” on your paper 3 times

2. Say, “kilohectodecaunitdecicentimilli” 10 times (in your head…or out loud…)

3. You will need to be able to say it without looking at your paper before you leave today!

Bring your book and a calculator tomorrow!

CFCs• What is being

measured on the x-axis?

• What is being measured on the y-axis?

• How is the Global CFC consumption related to CFCs in Antarctica?

CFC’s were used in refrigerants, plastics, & propellants in spray cans (and inhalers!)

9/__/09 Chapter 1What kinds of research do scientists do?

•Pure research seeks to gain knowledge for the knowledge itself.

•Applied research: seeks to solve a specific problem.• CFCs interact with ozone, stripping

it of oxygen molecules

Write this down!

9/__/09 Chapter 1Problem solving, the scientific way.

•Process is ongoing until hypothesis is either proven, or discarded.

1. Observe/gather info2. Make hypothesis3. Design/plan experiments4. Conduct experiments5. Analyze results6. Develop theory or scientific law

Write this down!

A systematic approach.

What is the difference between a theory and a scientific law?

Which is which?

• A store employee noticed that the tropical fish in one aquarium (called”A”) were especially colorful and healthy. He decided to conduct an experiment to determine why these fish were in such great condition.

• His 1st question, was to see if the total # of fish in the aquarium had an effect. Control group(s)? Experimental group(s)? Constant(s)? Independent variable(s)?

– A. Aquariums with the same amount of fish as kept in aquarium A.

– B. The number of fish in an aquarium.– C. Aquarium with more or less fish than in aquarium A.– D. Species of fish, diets, type of plants.

9/__/09 Parts of an experiment

Control group • Used for measure change against• Sets the standard for comparison• “normal” or un-altered• 1 group

Experimental group

• Groups where there is manipulation of the variable present

• more than 1 group

Constants • Same for all groups• Can be conditions (temp, light level) or

amount of something (water, nutrients)

Variable(s) • What is changing in each experimental group

• Can be conditions (temp, light level) or amount of something (water, nutrients)

Write this down!

Identify the parts of the following experiment:

GROUP NUMBERHEART BEATS

BEFORE THE TESTHEART BEATS AFTER

THE TEST1 73 80

2 74 89

3 71 97

4 75 76

Scientists wanted to know how caffeine changed the heart beat in humans. The scientists thought it would increase the number of heart beats. Four groups of humans were tested. There were 25 organisms in each group. Group 1 was given 1mg of caffeine, Group 2 was given 2mg, Group 3 was given 3mg, and Group 4 was given no caffeine. The heart beats of the groups were checked 30 minutes after they took the caffeine. The data is shown below.

Chapter 2 Analyzing Data

2.1 Units and Measurements

Measurement

You are making a measurement when you

¨ Check you weight

¨ Read your watch

¨ Take your temperature

¨ Weigh a cantaloupe

What kinds of measurements did you make today?

Common Tools for Measurement

Learning Check

From the previous slide, state the tool (s) you would use to measure

A. temperature ____________________

B. volume ____________________

____________________

C. time ____________________

D. weight ____________________

Solution

From the previous slide, state the tool (s) you would use to measure

A. temperature thermometer

B. volume measuring cup, graduated cylinder

C. time watch, clock

D. weight scale, triple beam balance

Measurement in Chemistry

In chemistry we

¨ do experiments

¨ measure quantities

¨ use numbers to report measurements

9/__/09 Ch. 2 - Measurements

What is a measurement exactly?

• When we measure, we use a measuring tool to compare some dimension of an object to a standard.

• In every measurement, there is a number followed by a unit.

The metric system (SI)

• Is a system based on 10• Used in most of the world• Used by scientists and hospitals

Write this down!

Learning Check

What are some U.S. units (not SI) that are used to measure each of the following?

A. length

B. volume

C. weight

D. temperature

Solution

Some possible answers are

A. length inch, foot, yard, mile

B. volume cup, teaspoon, gallon, pint, quart

C. weight ounce, pound (lb), ton

D. temperature °F

Units in the Metric System

length ---- meter m

volume ---- liter L

mass ---- gram g

temperature --- Celsius °C

Kelvin K

Learning Check

What is the unit of measurement in each of the

following examples?

A. The patient’s temperature is 102°F.

B. The sack holds 5 lbs of potatoes.

C. It is 8 miles from your house to school.

D. The bottle holds 2 L of orange soda.

Solution

A. °F (degrees Fahrenheit)

B. lbs (pounds)

C. miles

D. L (liters)

Learning Check

Identify the measurement in metric units.

A. John’s height is

1) 1.5 yards 2) 6 feet 3) 2 meters

B. The volume of saline in the IV bottle is

1) 1 liters 2) 1 quart 3) 2 pints

C. The mass of a lemon is

1) 12 ounces 2) 145 grams 3) 0.6 pounds

Solution

A. John’s height is

3) 2 meters

B. The volume of saline in the IV bottle is

1) 1 liter

C. The mass of a lemon is

2) 145 grams

Complete this table in your notes Do you see a pattern?

• Kilo (k) = 1,000• Hecto (h) = 100• Deca (da) = ____• Unit (l, m, g) = 1• Deci (d) = ____• Centi (c) = ____• Milli (m) = .001

So how does this work?

• Kilo (k) + meter (m) = km• Milli + liters = ml• Unit = whatever the unit is; liters = l

Convert the following:

• If you can remember: kilohectodecaunitdecicentimilli, it is very easy, use your pencil and make a u-shape whatever direction you need to go.

1. 500 km = ____ m

2. 10 cm = ____ mm