The Art of Polarity (Mary Eckel)

Chemistry at the LA River School

Title: The Art of Polarity: Looking at interactions between polar and non-polar molecules

Principle(s) Investigated: List all principles that apply to this activity.

Standards : Past in the appropriate California content standards.

Materials: See link above

Procedure: See link above

Student prior knowledge: Students prior knowledge should include what makes ionic and covalent bonds, properties of ionic and covalent bonds and a definition of polar and non-polar

Explanation: Give a thorough explanation of the experiment or demonstration. Your explanation should be written to give your fellow teachers a solid understanding and include greater detail than what you might provide for your secondary students. Make certain to include equations whenever pertinent.

Questions & Answers: Give three thought-provoking questions and provide detailed answers.

Applications to Everyday Life:

Stain Removers: "Like dissolves like". Grease stains are made of hydrocarbons and can be removed with a hydrocarbon solvent

Soap: Soap is a surfactant! The long hydrocarbon tails surround the grease/oil, while the small polar heads mix with the water. This grease/soap complex is water soluble, so it now can be washed away! This process is called emulsification.

Decaffeinating Coffee: Carbon dioxide is made into a supercritical fluid (fills a container like a gas and dissolves stuff like a liquid). This fluid is non-polar! When coffee beans are exposed to the supercritical carbon dioxide, the gas-like properties move through the beans while the liquid-like properties dissolve 97-99% the non-polar caffeine.

Nail Polish Remover (with acetone): Nail polish is non-polar and so is acetone is non-polar, which is why it is commonly used in nail polish remover.

Water: Water is polar!!!!!!!!!!! Universal solvent, capillary action, ice floats, membrane structures, surface tension

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