Bell Ringer: 1. What is a compound? 2. Is Oxygen a Taker or a Giver? Show your work. 3. Is Beryllium a Taker or a Giver? Show your work. 4. What kind of bond would K and Sc have? Show your work. 5. Count the atoms in the following compounds C 6 H 12 O 6 2C 3 H 4 O 3 3C 7 H 5 (NO 2 ) 3

The Molecule of Life! QaQ6k

Joke of the Day:

Why is it so important? Single most abundant compound in all living things.

What is a Polar Molecule? Polar Molecule: a molecule that has a positive and a negative side like a magnet

Why is Water a Polar Molecule? The oxygen atom is at one end and the hydrogen atoms are at the other. The Electrons spend more time around the Oxygen side giving a negative charge and less time around the Hydrogen side giving a positive charge.

Water is held together with Hydrogen Bonds Because of the positive and negative ends, water molecules can attract each other like magnets. Not as strong as Ionic or Covalent bonds

Water is Magnetic Demo!

Cohesion Cohesion: the attraction between molecules of the same substance. Water molecules LOVE to stick together. Causes molecules on the surface of water to be stuck together (making like a film on top of the water). This is called Surface Tension. Why water forms drops on a smooth surface Why insects can walk on water.

Adhesion Adhesion: an attraction between molecules of different substances. Water molecules are attracted to other substances such as glass. Causes water drops to stick to glass windows, etc. Why a meniscus forms in a graduated cylinder. Capillary action: ability of water to move against the flow of gravity. How plants get water to move from their roots to their leaves.

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- + + Water Molecule “The Sticky Molecule” E E E E E E E E E E P:8 N:8 O P:1 N:0 H P:1 N:0 H