Water: Who Wants Water: Who Wants Some?!?!Some?!?!

Water UnitWater Unit

Chemistry and SocietyChemistry and Society

McCollum/LehnerMcCollum/Lehner

Introduction to HIntroduction to H22OO

• TriviaTrivia– It takes 3.909 x 10It takes 3.909 x 104 4

gallons of water to gallons of water to make a new carmake a new car. .

– Seventy-five percent of Seventy-five percent of the human brain is the human brain is water. water.

– One gallon of gasoline One gallon of gasoline can contaminate can contaminate approximately 750,000 approximately 750,000 gallons of water. gallons of water.

Introduction (Cont.)Introduction (Cont.)

• On the average, On the average, each American uses each American uses about 160 gallons of about 160 gallons of water a day at a cost water a day at a cost of 27 cents. of 27 cents.

• Bottled water may Bottled water may cost up to 1000 cost up to 1000 times more than times more than municipal may not municipal may not be as safe. be as safe.

• An acre of corn An acre of corn contributes more to contributes more to humidity than a lake humidity than a lake of the same size. of the same size.

• The United States The United States consumes water at consumes water at twice the rate of twice the rate of other industrialized other industrialized nations. nations.

Why is Water Special??Why is Water Special??

• Physical Properties:Physical Properties:– Exists in all 3 states Exists in all 3 states

naturallynaturally– It is less dense as a It is less dense as a

solid than liquid (ice solid than liquid (ice floats)floats)

– It absorbs lots of It absorbs lots of heat (use as coolant heat (use as coolant and weather effect)and weather effect)

Images courtesy of: www.oceansonliImages courtesy of: www.oceansonline.comne.com

Why is Water Special??Why is Water Special??

• Chemical Chemical Properties:Properties:– Polar (makes great Polar (makes great

solvent)solvent)• High surface tensionHigh surface tension

• High boiling pointHigh boiling point

– Natural pH of 7Natural pH of 7

www.epa.govwww.epa.gov

Foul Water Activity (A.2)Foul Water Activity (A.2)

• Why is it Why is it important to important to have clean have clean water? water? – Katrina WateKatrina Wate

r Issuesr Issues

Foul Water Activity (A.2)Foul Water Activity (A.2)

• Procedure is on pg.7 Procedure is on pg.7 of your book.of your book.

• ObjectivesObjectives– Know:Know:

• what each of the 3 what each of the 3 separation methods separation methods are supposed to are supposed to remove from waterremove from water

• what types of things what types of things ARE NOT removed via ARE NOT removed via the separation the separation methods we usedmethods we used

• how DISTILLATION how DISTILLATION works, and what it works, and what it removes from waterremoves from water

Water Diary (A.3)Water Diary (A.3)

• We are going to We are going to construct a water construct a water diary over the next diary over the next few days in order few days in order to determine how to determine how much water you much water you use per day!use per day!

Data Table ExampleData Table Examplepage 11 of Textpage 11 of Text

UsageUsage Day 1Day 1 Day 2Day 2 Day 3Day 3

# of Persons in # of Persons in familyfamily

Number of bathsNumber of baths

Number of Number of washing machine washing machine loads:loads:

LowLow

HighHigh

Water and Health (A.4)Water and Health (A.4)

• All living organisms All living organisms need water in need water in order to survive.order to survive.– Humans can survive Humans can survive

roughly 50-60 DAYS roughly 50-60 DAYS without food, but without food, but only 5-10 days only 5-10 days without waterwithout water

– On average, On average, humans drink about humans drink about 2L of water per day2L of water per day

Don’t Drink The Water!!!Don’t Drink The Water!!!

• Early peoples Early peoples drank from rivers drank from rivers and streams.and streams.– As pop. Increased As pop. Increased

so did pollutionso did pollution– Wastes from farms, Wastes from farms,

industries, and industries, and other sources other sources contaminate water contaminate water sourcessources

Water….What is it Good Water….What is it Good For?For?• Each day 4.0 x 10Each day 4.0 x 1012 12

gallons of water gallons of water falls to the Earth as falls to the Earth as rain or snow, rain or snow, humans use 10%.humans use 10%.

• Where does it Where does it go???? go????

Usage Across US (East Side Vs Usage Across US (East Side Vs West Side)West Side)

• East Side!East Side!– 88% of water returned to natural water 88% of water returned to natural water

waysways– Most usage in manufacturing and Most usage in manufacturing and

homes/officeshomes/offices

Mississippi River DeltaMississippi River Delta

East Side Vs. West Side (Cont)East Side Vs. West Side (Cont)

• West Side!!West Side!!– Only 48% of water returned to Only 48% of water returned to

waterwayswaterways– Most water is used for irrigation (90%)Most water is used for irrigation (90%)– High evaporation rates (deserts)High evaporation rates (deserts)

The Untamed ColoradoThe Untamed Colorado

What’s the Difference?What’s the Difference?

• Eastern half gets more rainEastern half gets more rain

• Has more natural water suppliesHas more natural water supplies

• Wind FactorsWind Factors

How much water do we How much water do we use??use??

• Direct: Measured useDirect: Measured use– About 1360 L/Day (360 Gallons) per About 1360 L/Day (360 Gallons) per

family of fourfamily of four

• Indirect: Used in productionIndirect: Used in production– Example: Water consumed by cows that Example: Water consumed by cows that

make up that “Tasty Burger” from the make up that “Tasty Burger” from the “Hawaiian Burger Joint”“Hawaiian Burger Joint”

Which is more water use?!?!Which is more water use?!?!

• Drinking One bottle Drinking One bottle of “Fiji” water or a of “Fiji” water or a bottle of “Naked bottle of “Naked Fruit Juice”?Fruit Juice”?– Why?Why?

Back Through The Pipes Back Through The Pipes (A.6)(A.6)• Surface WaterSurface Water

– Rivers, lakes, etcRivers, lakes, etc

• Ground WaterGround Water– WellsWells

• AquifersAquifers– Rock layers that hold water undergroundRock layers that hold water underground– Springs, etcSprings, etc– Most abundant sourceMost abundant source

What’s in it?!?!What’s in it?!?!

• No Natural water is pureNo Natural water is pure– It conducts electricity, remember?It conducts electricity, remember?– Dissolves soil and rockDissolves soil and rock

• Iron, calcium, potassium, carbonates, Iron, calcium, potassium, carbonates, silicates, etcsilicates, etc

What’s the difference?What’s the difference?

Where did Water first come Where did Water first come from?from?

• VolcanoesVolcanoes

• CometsComets

• Condensation of Condensation of Atmospheric waterAtmospheric water

Phases Of WaterPhases Of Water

• SolidSolid– Lowest Kinetic EnergyLowest Kinetic Energy– Crystalline StructureCrystalline Structure

• LiquidLiquid– Loose Structure Loose Structure – Higher Kinetic EnergyHigher Kinetic Energy

• GasGas– No StructureNo Structure– Highest Kinetic EnergyHighest Kinetic Energy