2/23/12 A/B DayLEQ: How does the polarity of waterinfluence its physical properties?1. What is buoyancy?2. What is surface tension?3. What is more dense—warm water or coldwater?4. Why do we call water the universal solvent?5. Copy and complete: Water’s [high/low]specific heat means that it requires a [high/low]amount of heat for water to get hot!
Today’s LEQ: How does the polarity ofwater influence its physical properties?By the end of today, you should be able to…1. Describe the polarity of water.2. Explain why polarity creates cohesion and adhesion of water
CONTEXT CLUES:“Those two twins are polar opposites. They are nothing alike.”“The cowboys are such a cohesive team. They practice together, play together, and even eat all of their meals together!”“The stickers that you put on your car have two sides—one side has a design on it and the other side is the adhesive side.” Stop and Jot: Write your own definition of
Draw this in your notes:Polarity:Cohesion: Adhesion:
Draw this in your notes:Polarity: uneven charges in a watermolecule; causes water to be sticky!Cohesion: Adhesion:
Water sticks to itself.Water sticks to other stuff.
Draw this in your notes:Polarity: uneven charges in a watermolecule; causes water to form bonds!Cohesion: the Adhesion:tendency for watermolecules to stick toother water moleculesEx. Water drops sticktogether
Cohesion Demo:Can you get water to stick to itself?Make a C with your fingers
Surface Tension—this happens because of COHESION!
Draw this in your notes:Polarity: uneven charges in a watermolecule; causes water to form bonds!Cohesion: the Adhesion: thetendency for water tendency of water tomolecules to stick to stick to otherother water molecules substancesEx. Water drops stick Ex. Water sticks totogether other things
Adhesion Demo: Can you get water to stick to other stuff?Make a C with your fingers
Adhesion—water sticks to the side of a straw Adhesion
WaterOther stuff! Water Water
Water sticks to a spider web
Water sticks together over the edge of a glass
Water has uneven charges
Water stays together on saran wrap
Water sticks together in drops
Water sticks to blood cells
Water creates bonds
Water sticks to a windshield
Water sticks to a leaf
Water has a positive and negative end!
Water ripples do not break the surface
Use your notes and your new knowledge to add on to your water bubble map! Physical Properties WATERPolarity
Summarizer:1. What is polarity?2. What is the difference between cohesion and adhesion?3. Water sticking to the side of a glass—is this an example of cohesion or adhesion?4. Water sticking to another drop of water—is this an example of cohesion or adhesion?