Characteristics of Water
Where’s My Water?1. Fill a beaker with 100mL of water. This represents all water
on Earth.2. How much of the water do you think is contained in saltwater?
• Measure using the graduated cylinder.
3. Pour 97 mL of water into the graduated cylinder. 97% of all water is “trapped” as saltwater.• Dump out the 97 mL of water.
4. How much of the remaining water is in polar ice and glaciers? • Measure with the graduated cylinder.
5. Pour 2 mL of water into the graduated cylinder. 2% of all available water is in polar ice and glaciers.• Dump out the 2 mL of water
6. The remaining water represents the amount of freshwater on Earth. This includes water in reservoirs and lakes and underground.
Water:Covers ¾ of the Earth’s surface, but less than
half of one percent is available fresh waterSingle most abundant compound in most
living thingsExpands when freezes so ice is less dense
that waterhttp://
www.youtube.com/watch?v=2LAH7szGzJA
Chemical Properties of WaterThe Water Olympics
PolarityPresence of partial positive and negative charges causing attraction
• Due to an uneven distribution of electronics between the oxygen and hydrogen atoms
• Negative pole is near the oxygen and the positive pole between the hydrogen
• Greater probability of finding the shared electrons near the oxygen
Hydrogen Bonds: water glue•Hydrogen bonds occur in polar molecules containing hydrogen bonded to a highly electronegative atom (like water).
•The positive ends align with negative ends of other polar molecules
Does Soap Propel?How did that work?
Soap is an emulsifier.It interferes with the surface tension of water
by coming between water molecules
How Many Pennies?How did that work?
Water displayed cohesion and adhesion without the soap
When soap was introduced, it interfered with water cohesion and surface tension by coming between the water molecules.
Cohesion: attraction between molecules of the same substance
Adhesion: attraction between molecules of different substances
Capillary Action: tendency of water to rise in a thin tube
The Ventauri Effect: Fluids flow faster when forced through narrow spaces
Water OlympicsPenny DropsPour Water SidewaysWater StretchMerging StreamsWater TubesSoap Boat Race
Water: The Universal Solvent
MixtureA material composed of 2 or more elements or compounds physically combined
Solutions•If a crystal of table salt is placed in a glass of warm water, sodium and chloride ions on the surface of the crystal are attracted to the polar water molecules.
•Ions break away from the crystal and are surrounded by water molecules and become evenly distributed throughout (concentration).
Water’s Polarity Allows it to dissolve ionic compounds (ionic) and polar covalent compounds (sugar)
Hypothesize & InvestigateWhich compound, salt or sugar, will be more soluble in water?Why?
Water Has a High Specific HeatThe amount of energy needed to raise the
temperature of a substance 10CWater can absorb a large amount of heat
without significantly changing temperature.
Temperature and Earth’s Heat Budget LabUse Vernier to Analyze Graphs of Temperatures on Earth
Ice FloatsLess dense than water
Molecular motion slows during cooling allowing for formation of maximum number of hydrogen bonds
Crystal structure allows for air space
Air allows ice to insulate water below allowing for life to survive beneath
Frogsicles Project