Physical, chemical and biological properties of water
THE PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES OF WATER BUILDING UTILITIES: PLUMBING AND SANITARY SYSTEMS
ALL LIVING THINGS, FROM THE SMALLEST INSECT NEEDS WATER TOLIVE. EXPERTS PREDICT THAT BY 2025, 1/3 OF THE WORLDSPOPULATION WILL NOT HAVE WATER DUE TO THE INCREASE INPOPULATION AND WATER CONTAMINATION.EACH PERSON DISCHARGE ABOUT 200,000,000,000 COLIFORMS PERDAY. COLIFORM BACTERIA ARE THEREFORE VERY NUMEROUS-ANDTHE MOST COMMON AD WIDESPREAD HEALTH RISK ASSOCIATEDWITH DRINKING WATER IS MICROBIAL CONTAMINATION , THECONSEQUENCES OF WHICH MEAN THAT ITS CONTROL MUST ALWAYSBE OF PARAMOUNT IMPORTANCE.EARTH CURRENTLY HAS ESTIMATED 6.9 BILLION POPULATION AS OFJULY 1, 2011 BY THE UNITED STATES CENSUS BUREAU.
THE USES OF WATER:OUR WORLD IS A PLANET THAT IS DOMINATED BY WATER AND THROUGH THEYEARS THE DEVELOPMENT IN THE STUDY OF WATER HAS BEEN IMPROVEDAND PRACTICALLY TESTED. THERE ARE A LOT OF USES OF WATER AND THEFOLLOWING ARE JUST A FEW OF IT’S EXAMPLES.1. THE WATER IS ONE OF THE MOST IMPORTANT SOURCE OF A HUMAN LIFE.2. WATER IS THE HABITAT OF SEVERAL SPECIES.3. WATER SERVES AS OUR MAIN COURSE FOR THE HUMAN HYGIENE.4. WATER IS THE BASE OF ALL DRINKS AND BEVERAGES.5. ETC.
THE WATER AND ITS PROPERTIES THE PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES OF WATER
PHYSICAL PROPERTIES:Water has several other unique physical properties. These properties are:1. Water has a high specific heat. Specific heat is the amount of energy required tochange the temperature of a substance. Because water has a high specific heat, itcan absorb large amounts of heat energy before it begins to get hot.2. Water in a pure state has a neutral pH. As a result, pure water isneither acidic nor basic. Water changes its pH when substances are dissolved in it.
3. Water conducts heat more easily than any liquid except mercury. This fact causeslarge bodies of liquid water like lakes and oceans to have essentially a uniformvertical temperature profile.4. Water molecules exist in liquid form over an important range of temperaturefrom 0 - 100° Celsius. This range allows water molecules to exist as a liquid inmost places on our planet.5. Water is a universal solvent.6. Water has a high surface tension. In other words, water is adhesive and elastic,and tends to aggregate in drops rather than spread out over a surface as a thin film.This phenomenon also causes water to stick to the sides of vertical structuresdespite gravitys downward pull.
CHEMICAL PROPERTIES:Water’s chemical formula is H2O. The water molecule odd shape with bothhydrogen atoms occurring on the same side of the oxygen atom gives water itsability to “stick” to itself and to other surfaces. The hydrogen atoms create apositive electrical charge while the oxygen atom creates a negative charge. Theattraction to one another is what causes water to form droplets. The chemicalproperties make water essential to the functioning of living things including humanbeings. We must ingest or drink water in order to maintain good health.
This model of a water moleculeshows the arrangement of oneoxygen atom bound to two atoms ofhydrogen and their positive andnegative charges.Arranged water molecules positiveto negative charges make water“sticky” and from drops or beads ona smooth surface.
Water beads on hood of a carbecause of the arrangement ofwater molecules.
There is a clear correlation between access to safe waterand GDP per capita. However, some observers haveestimated that by 2025 more than half of the worldpopulation will be facing water-based vulnerability. Arecent report (November 2009) suggests that by 2030, insome developing regions of the world, water demand willexceed supply by 50%. Water plays an important role in theworld economy, as it functions as a solvent for a widevariety of chemical substances and facilitates industrialcooling and transportation. Approximately 70% offreshwater is consumed by agriculture.
CHEMICAL PROPERTIES:1. pH2. Alkalinity3. Total Hardness4. Iron, Manganese,5. Metal-Zinc, Copper, Chromium, Lead6. Nitrate/ Nitrite7. Arsenic, Fluoride8. Chloride9. Total and Free Chlorine
STANDARD VALUES FOR INORGANIC CHEMICAL CONSTITUENTS WITHHEALTH SIGNIFICANCE:CONSTITUENTS: MAXIMUM LEVEL REMARKS (mg/L)ARSENIC 0.05 FOR EXISTING WATER SUPPLY SYSTEM ARSENIC MAY BE NATURALLY OCCURRING IN WATER SOURCES. WHERE MAXIMUM LEVEL OF ARSENIC IS UNACHIEVABLE, CONCENTRATION IN WATER SUPPLY MUST BE KEPT AS LOW AS POSSIBLECADMIUM 0.003 CADMIUM IS USED IN MANUFACTURE OF STEEL, PLASTICS AND BATTERY AND RELEASE TO THE ENVIRONMENT THROUGH WASTEWATER OR FUMES. CADMIUM IS RELEASED IN WATER SUPPLY AS IMPURITY OF THE ZINC COATING OF GALVANIZED PIPES AND SOLDERS AND METAL FITTINGS.LEAD 0.01 LEAD MAY BE PRESENT IN WATER PRIMARILY FROM PLUMBING SYSTEMS CONTAINING LEAD PIPES, SOLDER, FITTINGS OR THE SERVICE CONNECTIONS TO THE HOMES
CONSTITUENTS: MAXIMUM LEVEL REMARKS (mg/L)NITRATE 50 NITRATE CONCENTRATION IN GROUNDWATER AND SURFACEWATER CAN REACH HIGH LEVELS AS A RESULT OF LEACHING OR RUN-OFF FROM AGRICULTURAL LAND OR CONTAMINATION FROM HUMAN OR ANIMAL WASTES. ANAEROBIC CONDITIONS MAY RESULT IN THE FORMATION AND PERSISTENCE OF NITRITE.NITRITE 3MERCURY 0.001 MRCURY IS USED IN THE INDUSTRIES SUCH AS IN THE ELECTROLYTIC PRODUCTION OF CHLORINE, IN ELECTRICAL APPLIANCES, IN DENTAL AMALGAMS AND AS A RAW MATERIAL FOR VARIOUS MERCURY COMPOUNDS. MERCURY OCCURS NATURALLY IN FRESHWATER AND GROUNDWATER IN THE INORGANIC FORM. METHYLATION OF INORGANIC MERCURY OCCURS IN FRESHWATER AND SEAWATER.CYANIDE 0.07 CYANIDES ARE OCCASIONALLY FOUND IN DRINKING WATER PRIMARILY AS A CONSEQUENCE OF INDUSTRIAL CONTAMINATION.ANTIMONY 0.02 ANTIMONY IS CONTAMINANT FROM PIPE AND FITTING MATERIALS. IT IS NOT A RAW WATER CONTAMINANT.
BIOLOGICAL PROPERTIES:1. Adhesion: water tends to stick unlike substances . Example is water sticking toblood vessels.2. Cohesion: which water molecules clings together due to Hydrogen bonding; thesurface film (top layer of water) is held by surface tension. Example is spilledwater forming a puddle.3. Solvency: water is considered a universal solvent for its ability to dissolve awide range of substance since it is a polar molecule. Example is salt or sugardissolving in water.
4. Chemical reactivity: water can participate in chemical reactions. Example:involvement of water molecules in dehydration synthesis and hydrolysis.5. Thermal stability: water has a high heat capacity, so it requires a lot of energy toheat up; requires 1 cal to raise 1 gram of water by 1 degree C. Example: stability ofthe oceans temperature during summer and winter.