Microanalysis in Science and Engineering

Identification of Solids

Physical Science

Contact Information

Susan Upton and Deborah Sells

supton@hotmail.com d_sells@hotmail.com

Livingston Academy

Performance Indicators

Physical Science Standards – State of TN– Standard 2.0 Structures and Properties of Matter

The student will be able to identify samples of matter as solid, liquid, gas, or plasma.

Textbook Reference

Foundations of Physical Science

Tom Hsu (CPO 2002)– Chapter 16 What is Matter ?

Internet References

Images used in this slide show were obtained from the following websites:

mayo http://anka.livstek.lth.se:2080/microscopy/gallery.htm snow http://www.anri.barc.usda.gov/emusnow/color/color.htm CO2 http://www.anri.barc.usda.gov/emusnow/MartianIce/ms.htm glass fracture surface http://www.bsu.edu/web/jcflowers1/rlo/lceramicsglass.htm

sea salt http://www.denniskunkel.com/PublicHtml/Details_PopUp.asp?File_Name=92558JWA sugar crystal (red) http://www.denniskunkel.com/PublicHtml/Details_PopUp.asp?File_Name=9287JWA diamond http://micro.magnet.fsu.edu/birthstones/pages/diamond.html acid crystals http://mse.iastate.edu/images/microscopy/AcidCrystalss.jpggypsum http://pubs.usgs.gov/of/2001/ofr-01-0429/sem1/ plastic http://www.unified-eng.com/semex/semex.html Various clip art images www.barrysclipart.comMouse detective clipart http://clipart.disneysites.com/display.php?catID=95Tupperware www.tupperware.comTennessee http://officialcitysites.org/stategov.php3?st=TN

The salt and sugar crystal micrographs were taken by us during the workshop at TTU.

Materials Needed

Materials Needed for this activity:– Samples of sugar, salt, glass, plastic– Hand lens– Textbook or web access

What Makes A Solid Be A Solid ?

Are These Solids ???

Investigation

1. Do you think each is a solid?

2. Look at each of the samples in front of you.

3. Why do you think each is or is not a solid?

Record your answers on your lab handout.

                                                                                          

Find the information

Look up the definition of a solid, either in your textbook or on the internet.

– One possible website is

http://www.howe.k12.ok.us/~jimaskew/pphase.htm

Write the definition on your lab handout.

Take a closer look

Now look at each sample using the hand lens.

Do you still agree with how you classified the samples originally?

Record your answers on your lab handout.

Take a really close look

Now you will look at pictures of each of the substances taken at high magnification using an electron microscope. This allows you to see more detail than possible with the human eye or the hand lenses.

After looking at the pictures, decide if your original classification of each substance fits the definition of a solid.

Record your answers on your lab handout.

SaltSugar

Glass Plastic

Explanation

Explain why each sample is or is not a solid, based on the definition of a true solid.

If a sample is not a true solid, what is it?– Use your textbook or the website to find out.

Record your answers on your lab handout.

Answers

The sugar and salt are true solids because they have a crystalline structure.

The glass and plastic are not true solids because they do not have a crystalline structure.– Amorphous refers to substances that appear to

be solid, but really aren’t, like the glass and plastic.

Now Try These

Now that you know what a true solid is, see if you can identify the following pictures.

Answers to “Now Try These”

If you said all of the samples were true solids, you missed one. The picture in the lower right hand corner is not a solid because is does not have a crystalline structure.

– The images were solid carbon dioxide (dry ice), sea salt, sugar, and mayonnaise.

Evaluation

Use the rubric to see how well you have mastered this material.

See if your self-assessment matches how well your teacher thinks you did.

Rubric

Excellent Good Satisfactory Poor

Following Directions

Student completes tasks without aide of teacher.

Student needs only limited guidance from teacher.

Student is unable to follow directions without repeated help from teacher.

Student needs constant teacher aide, unable to follow directions on own.

Correct Identification

Student identifies 100% of samples correctly

Student identifies 75- 90% of samples correctly.

Student identifies 50-75% of samples correctly.

Student identifies less than 50% of samples correctly.

Lab Procedures

Student follows correct lab safety procedures without being reminded.

Student follows correct lab procedures after being reminded.

Student must be repeatedly reminded of correct lab procedures.

Student does not follow correct lab procedures, even after being repeatedly reminded.

Ability to Access Information

Student is able to find information without assistance.

Student needs only limited help in finding information.

Student needs extensive help in finding information.

Teacher must find information for student.

End Notes

Special thanks to:– Dr. Margaret Phelps– Dr. Larry Knox– Dr. Chris Wilson– Dr. Joe Biernacki– Wayne Hawkins– The ever helpful graduate students