Chemical Properties and Interactions
Structure and Properties of Matter
Pure Substances
Activity
Matter can be divided into two categories: pure substances or mixtures.
A pure substance can be identified by its properties. A mixture can be
separated into two or more substances.
Investigate samples of several different types of matter to determine
whether each of sample is a pure substance or a mixture. Also give the
reasoning for your conclusion.
Procedure
A.  Salt Water and Distilled Water
1. Obtain samples of salt water and distilled water from your teacher.
2. Observe the two samples and record your observations in your lab journal.
3. Write down whether you think the distilled water is a pure substance and give your reasoning.
4. Write down whether you think the salt water is a pure substance and give your reasoning.
5. Use the masking tape and marker to label one black plastic plate “distilled water.”
6. Using an eye dropper, place five drops of distilled water onto the plate.
7. Label the other plate “salt water.”
8. Using a clean eye dropper, place five drops of salt water onto the plate.
9. Set the two plates under the lamp to evaporate.
10. Wash out the glassware and clean up your lab station.
11. After the water has evaporated from the plates, observe the two plates and record your
observations in your lab journal.
12. Answer the following questions in your lab journal to prepare for the class discussion.
a.  What do you think the residue is from the evaporation of the salt water?
b.  Do you think the residue is a pure substance? Why or why not?
13. Rinse the plates and save or recycle according to your teacher’s instructions.
B. Ink in a Black Marker
1. Obtain the materials needed from your teacher.
2. Measure 10 mL of water and pour into the test tube.
3. Place the test tube in the test tube rack.
4. Use the black marker to draw a thin line across the chromatography paper strip approximately 3
cm from one end.
5. Place the chromatography strip in the test tube with the marked end first. Be careful to keep the
marker line above the level of the water.
6. Observe what happens as the water rises up the paper.
7. Draw a picture of the final appearance of the chromatography paper in your lab journal and
answer the following questions.
a.  What do you think caused the color pattern seen on the chromatography paper?
b.  Do you think the ink from the black marker is a pure substance? Why or why not?
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Chemical Properties and Interactions
Structure and Properties of Matter
Pure Substances
Activity, continued
8.  Use tweezers to remove the chromatography paper from the test tube and set it aside to
dry.
9.  Wash the glassware and clean up your work area.
C. Iron and Sulfur
1.  Obtain a sample of iron and sulfur from your teacher.
2.  Carefully pour the sample onto a paper plate.
3.  Observe the sample and record your observations in your lab journal.
4.  Record whether you think this sample is a pure substance and explain your reasoning.
5.  Use the bar magnet to try to separate the iron and sulfur into two piles.
6.  Record your observations.
7.  Do you think the separated iron and sulfur piles are each pure substances? Why or why
not? Record your answer in your lab journal.
8.  Pour the iron filings and sulfur back into the cup for reuse, and clean up your work station.
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