+C: 17 Sept. 2010

Homework: Background info paragraphs

Objective: SWBAT test a hypothesis by collecting, organizing and analyzing data.

Do now: Rearrange this equation for

m= and V=V

mD

+Agenda

I. Do now

II. Lab introduction

III. Perform the lab!

IV. Data analysis, graphing and drawing conclusions

V. Intensive vs. extensive properties

Homework: Week 2/3 Homework p. 1-2

+

Density of Pennies Lab

+Density

A physical property of matter

The mass per volume of a substance.

Units: g/mL or g/cm3

1 mL = 1 cm3

density mass(g)

volume(mL /cm3)

+Calculate Density (or mass or volume)1. An object with mass of 10.0 g, and

volume of 20.0 mL

2. An object with mass of10.0 g and volume of 5 cm3

3. Calculate the mass of a sample of matter with a volume of 10.0 cm3 and density of 2.0 g/cm3

4. Calculate the volume of a rock with mass 100.0 g and density 5.00 g/mL.

+The phenomenon

In 1982, the density of pennies changed.

+Your challenge:Determine, empirically, the density of pennies before and after 1982.1. In your notebook (or piece of paper)

write two hypotheses.2. Carefully follow the procedure and

collect data in an organized table.3. Graph your data sets.4. Write an analysis paragraph

describing your graphed data sets.

+Some detailsHow can you determine the volume of a penny?

Displacement

Calculate the density of 2, 3, …10 pre-1982 pennies, and 2, 3, …10 post-1982 pennies. Make a neat table and graph.

+

+An example of a good table.Table 1: Mass, volume and density of pre-1982 penniesNumber of pennies

Mass (g) ±0.05g

Volume (mL) ±0.5 mL

Density (g/mL)

2

3

4

5

6

7

8

9

10

+Data to record:

2 Hypotheses

Data table for pre- and post-1982 pennies

Average density for each group

Graphs: mass vs. volume (2 sets of data on the same axes, do not connect dots!)

+Intensive vs. extensive propertiesIntensive property: a physical property that does NOT depend on how much of a substance you have.Ex: temperature, velocity, melting point

Extensive property: a property that DOES depend on how much you have.Ex: mass, length, volume

+Intensive or extensive?I weigh 130 pounds.

The car is moving 50 miles per hour.

The length of a marathon is 24.6 miles.

The density of water is 1.0 g/mL

Ice melts at 0oC.

I drank one liter of soda. (burp!)

+

So, is density intensive or extensive? How do you know? Discuss your graph, and what a graph of the other type might look like.

+Homework: Week 2/3 p. 1-2: Thurs.Week 2/3 Homework, #6 ADD PICTURES

+C: 17 Sept. 2010

Take out Homework: Graph of data

Objective: SWBAT graph data using Excel.

Do now: Describe two errors from your experiment yesterday. How could you make improvements to minimize this error?

+Agenda

I. Do now

II. Homework check

III. Graphing in excel

Homework: Write an analysis paragraph

+Making a graph

Follow along in Excel as Ms. Boiteau shows you how to enter your data, and then how to make a graph.

+A: 17 Sept. 2010

Get out Homework: None!

Objective: SWBAT graph data and communicate an analysis in a complete paragraph.

Do now: Log into your computer, open your email, and download your Excel file from yesterday.

+Agenda

I. Log in and download

II. Finish graphing: adding in the “details”

III. Print

IV. Analyze graphs and write an analysis paragraph

V. Notebooks!

Homework: Finish analysis paragraph, write a conclusion

+Writing an analysis of your data

Write a paragraph describing your two data sets, but not explaining what the data mean. What data is shown on your graph? What is the shape of the data? Slope? Are there any outliers? What are they?

+Writing a conclusionRestate hypothesis. Were your hypotheses supported by your data? Why or why not? Answer conclusion questions in a paragraph:

Is density an intensive or extensive property? How do you know? Give evidence from your data.

What elements are pennies made of? One of these elements has a density of 8.92 g/mL. How do your densities (before 1982 and after 1982) compare with the density of the pure element? Why do you think this is?

How do you explain any difference in the density of the two groups?

Use the results of this lab to make a hypothesis about how the composition (make-up) of the two groups of pennies is different. What do you think changed in 1982 (aside from density)? Why? (Connect conclusion to background info!!)

+Homework

Finish your analysis paragraph

Write a conclusionDue Monday.

Transfer notes into your new notebook (optional)(or bring $10 Monday for your notebook)

+Write a Lab Report

Title (incl. name, date, partner’s names)

Background info (from notes, etc.)

Objective (no hypothesis)

Due Friday

(You can start the procedure if you want!)

+Title

Your lab report should be titled with a title of your choosing.

It should be relevant to the lab and should not just be the same as the title of a handout your teacher gave you.

Do not have it on a separate title page.

+Background Information

Explain any important concepts that are central to understanding the experiment.

In paragraph form, define any scientific terms necessary for understanding the lab.

Link these concepts and terms together into a coherent paragraph

+Objective and Hypothesis

Explain what the purpose of the experiment or what goals you have in completing the lab. What do you hope to accomplish?

Predict the results of the experiment. Explain your reasoning behind your hypothesis.

State your independent, dependent and controlled variables.

+Procedure

For a lab where you have designed the procedure, include a detailed and complete account of every single step you completed during the lab, including how to make calculations. Be sure to include proper names for pieces of equipment!

If you have followed a procedure given by your teacher, write a summary of what you did. Do not rewrite the given procedure word for word.

+Data and Results

Include any charts, graphs, tables, technical drawings, observations, or diagrams in this section. Include a one sentence caption for each.

Data should be presented neatly, and with the use of computer software when possible.

If any calculations were necessary during this lab, include them here.

DO NOT explain the data.

Figure 1: Mass in grams vs. volume in mL of two groups of pennies (pre-1982 and post-1982) with a best-fit line.

+Analysis

Describe any patterns or trends in the data. Point out any relevant characteristics and comparisons that you see. Do not attempt to explain them, simply note them.

Note the existence of any data that does not seem to fit the overall patterns/trends (ouliers).

+Conclusions

Draw conclusions from the patterns and observations you noted in the analysis section. Explain why the patterns you saw occurred.

Was the experiment successful at completing the objectives above? Explain why or why not.

Reflect on your hypothesis. Was it correct? Why or why not?

Was there any significant error in your experiment? Propose some possible sources of error and explain how they might be improved.

Answer questions (4) in lab handout in paragraph form.

+

Lab Report Due Next MondayThis is your ONLY draftTyped!!This will be used as a ‘pre-test’ for your ability to write a lab report Will be compared to your lab reports as the

year goes on to measure your progress! This does count as a lab grade!

+

Hand back background info paragraphs!