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WATER, TAKEN IN MODERATION, CANNOT HURT ANYBODY. - Mark Twain -

WATER, TAKEN IN MODERATION, CANNOT HURT ANYBODY. - Mark Twain -. CYCLES ARE COMMON IN NATURE. WE EVEN SAW THEM IN ASTRONOMY. STARS HAVE A FINITE LIFETIME. THEY ARE BORN IN NEBULAS, THEY PRODUCE ENERGY, USE UP THEIR FUEL, AND DIE IN GIGANTIC EXPLOSIONS CALLED SUPER NOVA.

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WATER, TAKEN IN MODERATION, CANNOT HURT ANYBODY. - Mark Twain -

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  1. WATER, TAKEN IN MODERATION, CANNOT HURT ANYBODY. - Mark Twain -

  2. CYCLES ARE COMMON IN NATURE. WE EVEN SAW THEM IN ASTRONOMY. STARS HAVE A FINITE LIFETIME. THEY ARE BORN IN NEBULAS, THEY PRODUCE ENERGY, USE UP THEIR FUEL, AND DIE IN GIGANTIC EXPLOSIONS CALLED SUPER NOVA. THE DUST AND GAS IS SCATTERED IN SPACE AND EVENTUALLY FORMS INTO NEBULA, AND THE CYCLE BEGINS AGAIN.

  3. ON THE SURFACE OF THE EARTH, WE HAVE THE ROCK CYCLE. PLATE TECTONICS USE ENERGY FROM THE INTERIOR OF THE EARTH TO BUILD UP CONTINENTS AND MOUNTAINS. WEATHERING AND EROSION WEAR THE ROCK DOWN AND CREATE NEW ROCK THROUGH SEDIMENTATION.

  4. ROCKS ARE SUBDUCTED AS PLATES COLLIDE. THEY CAN BE MELTED AND COOLED TO MAKE IGNEOUS ROCK. OR, THEY CAN BE RECRYSTALLIZED THROUGH HEAT AND PRESSURE TO MAKE METAMORPHIC ROCK.

  5. THE WATER CYCLE IS PART OF THIS BATTLE OF FORCES THAT SHAPES THE SURFACE OF THE EARTH.

  6. THE SUN SUPPLIES THE ENERGY TO DRIVE THE WATER CYCLE. THERE ARE THREE WAYS WE CAN LOOK AT THE WATER CYCLE. - FIRST, WE COULD LOOK AT THE RESERVOIRS THAT CONTAIN THE WATER IN THE WATER CYCLE - SECOND, WE COULD LOOK AT THE RESIDENCE TIMES FOR WATER IN THE RESERVOIRS - THIRD, WE COULD LOOK AT THE PATHWAYS BETWEEN THE RESERVOIRS – HOW THE WATER MOVES BETWEEN THEM

  7. 97.5% OF ALL WATER ON EARTH IS SALT. 2.5% IS FRESH. 2.0% IS FROZEN (ICE CAPS OR GLACIERS) 0.592% IS GROUND WATER 0.014% IS RIVERS, LAKES, WATER VAPOR REMEMBER, 70% OF EARTH’S SURFACE IS COVERED WITH WATER – MOST OF IT SALT.

  8. THAT SEEMS LIKE A VERY SMALL AMOUNT OF WATER AS FRESH SURFACE WATER. HOWEVER, THE RESIDENCE TIME FOR A MOLECULE OF WATER AS WATER VAPOR IS VERY SHORT – ON AVERAGE ABOUT ONE DAY.

  9. WATER IS CONTINUALLY MOVING IN THIS CYCLE. THE RESIDENCE TIME OF A WATER MOLECULE AS SURFACE FRESH WATER COULD BE MEASURED IN YEARS. THE RESIDENCE TIME OF A WATER MOLECULE AS GROUND WATER COULD BE MEASURED IN THOUSANDS OF YEARS. EVENTUALLY, ALL WATER FLOWS BACK TO THE OCEANS. MOST OF THE WATER THAT WE HAVE ON EARTH HAS BEEN HERE FOR AT LEAST 4 BILLION YEARS. VERY LITTLE IS CREATED OR DESTROYED. IT IS SIMPLY REUSED.

  10. WATER IS A VERY UNUSUAL COMPOUND. IT IS A POLAR MOLECULE, AND THIS GIVES IT SOME SPECIAL PROPERTIES. IN A POLAR MOLECULE, THE CHARGES ARE NOT EQUALLY DISTRIBUTED, SO IT HAS A NEGATIVE END AND A POSITIVE END.

  11. SPECIAL PROPERTIES OF WATER: IT HAS A HIGH MELTING POINT AND BOILING POINT FOR ITS MASS IT IS A GREAT SOLVENT IT HAS A HIGH HEAT CAPACITY IT HAS A HIGH HEAT OF FUSION AND HEAT OF VAPORIZATION IT HAS A HIGH SURFACE TENSIION THE SOLID IS LESS DENSE THAN THE LIQUID

  12. SINCE WATER IS A POLAR MOLECULE, IF YOU PUT A BUNCH OF WATER MOLECULES TOGETHER, THE POSITIVE ENDS OF SOME WILL BE ATTRACTED TO THE NEGATIVE ENDS OF OTHERS. THIS GIVES THE MOLECULES AN ADDITIONAL “STICKEYNESS” THAT MANY SUBSTANCES DON’T HAVE.

  13. Melting Point Boiling Point Water, H2O Oo C 100o C Methane, CH4 -184o C -162o C WATER AND METHANE HAVE MOLECULAR MASSES THAT ARE SIMILAR, BUT THEY HAVE VERY DIFFERENT MELTING AND BOILING POINTS BECAUSE OF THE ADDITIONAL STICKEYNESS.

  14. HEAT CAPACITY IS THE AMOUNT OF HEAT REQUIRED TO RAISE THE TEMPERATURE OF 1 GRAM OF A SUBSTANCE 1 oC. WATER HAS A HEAT CAPACITY OF 1 CALORIE PER GRAM PER DEGREE. THIS MEANS THAT IT WOULD TAKE 100 CALORIES TO RAISE THE TEMPERATURE OF 1 GRAM OF WATER FROM 0oC TO 100oC. THIS HELPS PROVIDE THERMAL STABILITY TO OUR BODIES, AS WE ARE ABOUT 2/3 WATER.

  15. HEAT CAPACITY – 1 CALORIE PER GRAM PER DEGREE HEAT OF FUSION – 80 CALORIES PER GRAM (HEAT TO MELT 1 GRAM OF ICE) HEAT OF VAPORIZATION – 540 CALORIES PER GRAM (HEAT TO VAPORIZE 1 GRAM OF WATER TO WATER VAPOR) THE HIGH HEAT OF VAPORIZATION HELPS WHEN WE COOL THE BODY THROUGH SWEATING IN THE SUMMER.

  16. SOLID WATER IS LESS DENSE THAN LIQUID WATER. THIS WOULD BE VERY IMPORTANT IF YOU WERE A FISH.

  17. SURFACE TENSION IS THE ENERGY REQUIRED TO INCREASE THE SURFACE AREA OF A LIQUID. SURFACE TENSION IS DUE TO UNEQUAL FORCES AT THE SURFACE OF WATER. THERE ARE NO MOLECULES ABOVE THE SURFACE, SO ALL OF THE FORCES ARE DIRECTED TO THE SIDES AND DOWN.

  18. SURFACE TENSION IS WHY WATER DROPLETS ARE SPHERICAL. A SPHERE HAS THE HIGHEST VOLUME TO SURFACE AREA RATIO OF ANY SOLID. SURFACE TENSION IS ALSO WHY WATER SPIDERS CAN WALK ON THE SURFACE OF WATER.

  19. REVIEW OF THE SPECIAL PROPERTIES OF WATER: HIGH MELTING POINT AND BOILING POINT FOR ITS MOLECULAR MASS HIGH HEAT CAPACITY HIGH HEAT OF FUSION HIGH HEAT OF VAPORIZTION HIGH SURFACE TENSION WATER EXPANDS WHEN IT FREEZES GREAT SOLVENT

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