COMPOSITION ACTIVITY
Exploring Polarity &Background Polarity is a physical property that describes whether or not a substance contains polar molecules. A polar molecule has bonded in a way that has an uneven distribution of electrons, creating an electric field or charged ends. Polarity determines how well substances mix. Polar substances dissolve in other polar substances, while nonpolar substances dissolve in nonpolar substances.
? Question How do polar and nonpolar substances interact when mixed together?
Hypothesis Draft a hypothesis to answer the question using an “If...then...because...” format.
Materials 2 Foam and 2 biodegradable starch packing peanuts Acetone 2 100 mL Beakers
2 Stirring rods Safety goggles Water
Procedure 1. Obtain two packing peanuts labeled “A” and two labeled “B” from the instructor. 2. Record at least three different properties for each type of packing peanut. 3. Fill a 100 mL beaker with 50 mL of water and a second 100 mL beaker with 50 mL of acetone. 4. Put one “A” packing peanut into each beaker and stir. 5. Record whether the peanuts dissolve in acetone or water. 6. Put one “B” packing peanut into each beaker and stir. 7. Record whether the “B” peanuts dissolve in acetone or water. 8. Clean up according to your teacher’s instructions and answer the questions.
Data and Observations Packing Peanut Type
Action in Acetone
Action in Water
A B Analysis and Conclusions 1. Which solvent is polar? __________________ Which solvent is nonpolar? ____________How do you know? 2. Based on your observations, which peanut, A or B, is polar? How do you know? 3. Based on your observations, which peanut, A or B, is nonpolar? How do you know? 4. Ask the teacher for the identity of the materials from which the peanuts were made. The polar substance is _______________________ and the nonpolar substance is ________________. 5. Gasoline is made from refined petroleum, like many hydrocarbons, and is nonpolar. What would happen if it was transported in a styrofoam™ container? Explain why this is important.
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Exploring Oil and Natural Gas