Resolving Dissolving – Day 2 p. 119

Entry Task You have a friend who did not take IS1. At lunch, your friend drips butter on his/her favorite shirt. She/he runs to the bathroom to try to get the stain out with water. Draw a picture to show your friend why he/she will not be successful in removing the stain with water.

Resolving Dissolving Read “Other Polar Covalent Molecules” p.123-124 Take notes Remember to include a summary at the end! Do R&C #1-3 on page 124 - 125!

Other Polar Covalent Molecules Dipoles are the result of differences in the plus-minus nature of atoms. The strength of the dipole is determined by the electrical properties of the atoms that make up the molecule. Molecules that contain dipoles can attract each other. The strength of attraction depends on the strength of the dipoles involved.

Other Polar Covalent Molecules Molecules with dipoles interact because of their plus and minus parts. Molecules with dipoles will dissolve in each other (because their plus and minus parts interact).

Other Polar Covalent Molecules Sugar dissolves in water because parts of the molecule have a dipole.

Other Polar Covalent Molecules Most organic compounds are made of carbon rings. They contain dipoles (of different strengths) because there are “stronger” atoms bonded to the carbon. The dipoles make it so that these organic compounds are soluble in water.

Reflect & Connect #1 Does the statement All matter exhibits electrical properties mean that all matter conducts electricity? If the positive and negative charges are balanced and evenly distributed, the substance will exhibit an overall neutral electrical property and will not conduct electricity. Charges may be unevenly distributed, in which case the molecule will exhibit a dipole, but will still not conduct electricity because positive and negative charges are not free to move independently. Ionic compounds will conduct electricity in solution because the positive and negative charges (ions) that make it up are free to move in solution.

Reflect & Connect #2 p. 125 For the substances that you tested in Particular Properties, add another column “Microscopic Type” and fill it in. Explain.

Reflect & Connect #2 p. 125