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Density of Pennies Lab

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Intensive property: a physical property that does NOT depend on how much of a substance you have.
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Ex: temperature, velocity, melting point
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Extensive property: a property that
DOES depend on how much you have.
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Ex: mass, length, volume

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I weigh 130 pounds.
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The car is moving 50 miles per hour.
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The length of a marathon is 24.6 miles.
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The density of water is 1.0 g/mL
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Ice melts at 0 o C.
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I drank one liter of soda. (burp!)

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A physical property of matter
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(
)
(
/
3 )
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The mass per volume of a substance.
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Units: g/mL or g/cm 3
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1 mL = 1 cm 3

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Mass = 10.0 g, volume = 20.0 mL
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10.0 g, 5 cm 3
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Calculate the mass of a sample of matter with a volume of 10.0 cm 3 and density of 2.0 g/cm 3
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Calculate the volume of a rock with mass 100.0 g and density 5.00 g/mL.

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Week 6 Homework, #5-6

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In 1982, the density of pennies changed.

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Determine, empirically, the density of pennies before and after 1982.
1.
2.
3.
Write a materials list and procedure.
Include ALL your steps. Be thorough!
Carry out your procedure.
Record and organize data into a chart and graphs. Describe your data in a paragraph.
4.
5.
Analyze your data in a paragraph.
Make a conclusion summarizing your data and answering questions.

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How can you determine the volume of a penny?
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Displacement
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Calculate the density of 2, 3, …10 pre-
1982 pennies, and 2, 3, …10 post-1982 pennies. Make a neat table and graph.

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Table 1: Mass, volume and density of pre-1982 pennies
Mass (g) Volume (mL) Density
(g/mL)
Number of pennies
6
7
8
9
10
4
5
2
3

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An excellent materials list and procedure
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Complete data tables (title, headings, units, calculations, NEATLY!)
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Complete graphs: mass vs. volume and
EITHER mass vs. density or volume vs. density, with title, axis labels and units
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A written description of your data.
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A written analysis of your data
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A conclusion based on guiding questions.

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To write a lab report.
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First Draft (neatly hand-written or typed) due:

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

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Materials list and procedure (incl. how to make calculations!)
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Data table for pre- and post-1982 pennies
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2 graphs: mass vs. volume AND either
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Mass vs. density OR volume vs. density
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With a sentence describing each graph.
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You can start an analysis and conclusion like we practiced yesterday.

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Week 6 Homework: #5-6
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2 graphs: mass vs. volume AND either
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Mass vs. density OR volume vs. density
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With a sentence describing each graph.
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You can start an analysis and conclusion like we practiced yesterday.

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Not talking when another person is talking.
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Not making distracting noises (incl. with your chair), faces or gestures.
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Staying on task; following directions.

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1.
Warning
2.
Warning/email to advisor
3.
Email to advisor/call home
4.
Email to advisor/call home/IR
For behavior within one week!

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Arguing or being disrespectful
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“Get outta my face!” “Whatever.” “I wasn’t doing anything!” “It wasn’t me!”
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This will cause you to go to the next consequence.
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Talk to me after class. This will NOT cause you to get into more trouble.

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YOU are responsible for your behavior, no matter what anyone else is doing.
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I know you’re not the only one, but you caught my attention for being the first/loudest/most frequent/least respectful violator.

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If you don’t do your homework (either checked in class or collected), assume you have a homework detention.
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If you finish the work, you must have me sign a “Homework Detention
Rescind Form.”
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This starts TODAY

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 www.phascience.wordpress.com
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Assignment Sheets!
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How to write a lab report!
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The Density of Pennies PowerPoint
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Yay!

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Title (incl. name, date, partner’s names)
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Background info (from notes, etc.)
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Objective (no hypothesis)
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Due Friday
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(You can start the procedure if you want!)

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Your lab report should be titled with a title of your choosing.
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It should be relevant to the lab and should not just be the same as the title of a handout your teacher gave you.
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Do not have it on a separate title page.

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Explain any important concepts that are central to understanding the experiment.
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In paragraph form, define any scientific terms necessary for understanding the lab.

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Explain what the purpose of the experiment or what goals you have in completing the lab. What do you hope to accomplish?
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(No hypothesis)
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IV: number of pennies
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DV: density (explain why!)

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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!
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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.

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Include any charts, graphs, tables, technical drawings, observations, or diagrams in this section. Include a one sentence caption for each.
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Data should be presented neatly, and with the use of computer software when possible.
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If any calculations were necessary during this lab, include them here.
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DO NOT explain the data.

4
3,5
3
2,5
2
1,5
1
0,5
0
0
Mass vs. Volume of Pre- and Post-1982 Pennies
Pre-1982 Pennies Post-1982 Pennies
5 10 15
Mass (g)
20 25 30 35

10,0
9,0
8,0
7,0
6,0
5,0
4,0
3,0
2,0
1,0
0,0
0
Mass vs. Density of Pre- and Post-1982 Pennies
Pre-1982 Pennies Post-1982 Pennies
5 10 15
Mass (g)
20 25 30 35

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Fix your graphs. Draw a best-fit line.
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Write a one-paragraph analysis for each graph. Describe BOTH lines for each graph.
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Trend
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Shape of line
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Outliers: points that are way off the line.

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

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Draw conclusions from the patterns and observations you noted in the analysis section.
Explain why the patterns you saw occurred.
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Was the experiment successful at completing the objectives above? Explain why or why not.
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Reflect on your hypothesis. Was it correct?
Why or why not?
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Was there any significant error in your experiment? Propose some possible sources of error and explain how they might be improved.
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Answer questions (4) in lab handout in paragraph form.

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Write the first draft of your lab report.
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Work on your own.
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You may listen to music as long as I can’t hear it.
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Label each section.
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Be careful to include EVERY part listed in your lab report guide.
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First draft due: next Thursday, Oct. 22