ENVIRONMENTAL CHEMISTRY

INDEX 1 .ENVIRONMENTAL CHEMISTRY

2 .ATOMOSPHERIC POLLUTION3 .TROPOSPHERIC POLLUTION4 .STRATOSPHERIC POLLUTION

5 .THE OZONE HOLE6 .WATER POLLUTION

7 .SOIL POLLUTION8 .INDUSTRIAL WASTE

9 .STRATEGIES TO CONTROL ENVIRONMENTAL POLLUTION

ENVIRONMENTAL POLLUTION“ENVIRONMENTAL POLLUTION” IS THE EFFECT OF

UNDESIRABLE CHANGES IN OUR SURROUNDINGS THAT HAVE HARMFUL EFFECTS ON PLANTS,ANIMALS AND HUMAN BEINGS. A SUBSTANCE, WHICH CAUSES POLLUTION IS KNOWN AS POLLUTANT POLLUTANTS CAN BE LIQUID,SOLID

AND GASEOUS SUBSTANCES PRESENT IN GREATER CONCENTRATION THAN IN NATURAL

ABUNDANCE AND ARE PRODUCED DUE TO NATURAL HAPPENINGS

OR HUMAN ACTIVITIES .

ATMOSPHERIC POLLUTIONAIR POLLUTION IS DEFINED AS ADDITION OF UNDESIRABLE MATERIALS INTO THE ATMOSPHERE EITHER DUE TO NATURAL PHENOMENA AND HUMAN ACTIVITY ON EARTH WHICH ADVERSLY AFFECTS THE QUALITY OF AIR AND HENCE AFFECTS LIFE ON EARTH.IT IS KNOWN AS ATMOSPHERIC POLLUTION.

ATMOSPHERIC POLLUTION IS USUALLY \STUDIED AS STRATOSPHERIC AND

TROPOSPHERIC POLLUTION.

TROPOSPHERIC POLLUTIONTROPOSPHERIC POLLUTION OCCURS DUE TO THE PRESENCE OF UNDESIRABLE SOLID OR GASEOUS PARTICLES IN THE AIR. THE FOLLOWING ARE THE MAJOR GASEOUS AND PARTICULATE POLLUTANTS PRESENT IN THE TROPOSPHERE:

GASEOUS AIR POLLUTANTS:THESE ARE OXIDES OF SULPHUR,NITROGEN,AND CARBON,HYDROGEN SULPHIDE, HYDROCARBONS,OZONE AND OTHER OXIDANTS.PARTICULATE POLLUTANTS: THESE ARE DUST ,

FUMES,SMOKE,SMOG ETC.

GLOBAL WARMING AND GREEN HOUSE EFFECT

INCREASE IN CONCENTRATION OF CARBON DI OXIDE WHICH ISEMITTED BY AUTOMOBILES,INDUSTRIES ETC,INCREASE IN CONCENTRATION OF METHANE WHICH IS EMITTED WHEN VEGETATION IS BURNT, PADDY FIELDS, COAL MINES ETC.INCREASE IN CONCENTRATION OF CFC’S WHICH IS COMMONLY

PRODUCED OR EMITTED BY REFRIGIRATORS, A.C.s ETC.WHEN THE Ph OF RAIN WATER BECOMES 5.6 TO THE PRESENCE OF H +

IONS FORMED BY THE REACTION OF RAIN WATER WITH CARBON DIOXIDEPRESENT IN THE ATMOSPHERE AND RESULTS IN ACID RAIN.ACID RAIN IS HARMFUL FOR AGRICULTURE,TREES AND PLANTS AS IT

DISSOLVES AND WASHES AWAY NUTRIENTS FOR ITS GROWTH, ACID RAIN ALSO EFFECTS THE AQUATIC LIFE, DRINKING WATER

AND BUILDINGS AND OTHER STRUCTURES .

PARTICULATE POLLUTANTS

PARTICULATES POLLUTANTS ARE THE MINUTE SOLID PARTICLESOR LIQUID DROPLETS IN AIR.THESE ARE PRESENT IN VEHICLE EMISSIONS,SMOKE PARTICLES FROM FIRES,DUST PARTICLESAND ASH FROM INDUSTRIES.PARTICULATES IN THE ATMOSPHERE MAY BE VIABLE OR NON VIABLE.THE WORD SMOG COMES FROM SMOKE AND FOG.THIS IS THE MOST COMMON EG.

OF AIR POLLUTION THAT OCCURS IN MAINLY CITIES THROUGHOUT THE WORLD.CLASSICAL SMOG OCCURS IN COLD AND HUMID CLIMATE IT IS A MIXTURE OF

SMOKE,FOG AND SULPHUR DIOXIDE.PHOTO CHEMICAL SMOG OCCURS IN WARM,DRY AND SUNNY CLIMATE.THE MAIN

COMPONENTS OF PHOTOCHEMICAL SMOG RESULTS FROM THE ACTION OF SUNLIGHTON UNSATURATED HYDRCARBONS AND NITROGEN OXIDES. THE EFFECTS OF PHOTOCHEMICAL SMOG IRRITATES THE NOSE AND THROAT AND HIGH CONC.

CAN CAUSE HEADACHE.PHOTOCHEMICAL SMOG CAN BE CONTROLLED BY PRIMARY AND SECONDARY PRECURSORS SUCH AS HYDROCARBONS,OZONE

AND PAN.CERTAIN PLANTS SUCH AS PINUS, JUNIPARUS CAN METABOLISE NITROGEN OXIDE AND THEREFORE THEIR PLANTATION COULD HELP IN THIS

MATTER.

OZONE LAYERIN 1980s ATMOSPHERIC SCIENTISTS IN ANTARTICA REPORTED ABOUT THE DEPLETION OF THE OZONE LAYER.IN THE SUMMER SEASON, NO2 AND METHANE REACT WITH CHLORINE MONOXIDE AND CHLORINE ATOMS FORMING CHLORINE SINKS PREVENTING MUCH CHLORINE DEPLETION. IN WINTER SEASON A STRATOSPHERIC CLOUD IS FORMED PROVIDING ON WHICH CHLORINE NITRATE GETS HYDROLYSED TO FORM HYPOCHOLORUS WHICH REACTS WITH HYDROGEN CHLORIDE TO FORM MOLECULAR CHLORINE. WITH THE DEPLETION OF OZONE LAYER MORE UV RADIATION FILTERS INTO THE TROPOSPHERE. UV RADIATIONS LEAD TO AGEING OF SKIN,CATARACT, SUNBURN, SKIN CANCER,DAMAGE TO FISH PRODUCTIVITY ETC.

THE PLANT PROTEIN GETS EASILY AFFECTED WHICH LEADS TO THE HARMFUL MUTATION OF PLANTS AND CAN ALSO FADE THE CCOLOR OF WALL PAINTS AS WELL

WATER POLLUTIONWATER IS ESSENTIAL FOR OUR LIFE. POLLUTION OF WATER ORIGINATES FROM HUMAN ACTIVTIES.EASILY IDENTIFIED POLLUTION IS CALLED AS A POINT SOURCE. CAUSES OF WATER POLLUTION CAN BE THROUGH PATHOGENS,ORGANIC WASTES AND CHEMICAL POLLUTANTS.THERE ARE INTERNATIONAL STANDARDS FOR DRINKING WATER AND THUS DIFFERENT ELEMENTS SHOULD HAVE THE CORRECT AMOUNT OF CONC.

FLORIDE:-EXCESS IN FLOURIDE COMPOSITION CAN CAUSE TOOTH DECAYLEAD:-EXCESSIVE CONTAMINATION OF LEAD CAN DAMAGE LIVER,KIDNEY AND THE REPRODUCTIVE SYSTEM.

SULPHATE:- EXCESSIVE AMOUNT OF SULPHATE CAN CAUSE LAXATIVE EFFECT.NITRATE:- EXCESS NITRATE CAN CAUSE BLUE BABY SYNDROME

SOIL POLLUTIONSOIL POLLUTION IS CAUSED BY PRESENCE OF XENOBIOTIC(HUMAN

MADE) CHEMICALS OR OTHER ALTERATIONS IN THE NATURAL SOIL AND ENVIRONMENT. CAUSES FOR SOIL POLLUTION IS PESTICIDES:PESTICIDES

ARE BASICALLY SYNTHETIC TOXIC CHEMICALS WITH ECOLOGICAL REPERCUSSIONS. BUT THESE TOXICS ARE INSOLUBLE AS WELL AS NON

BIODEGRADEABLE AND HARM THE FOOD CHAIN FROM LOWER TO HIGHER TROPHIC LEVEL.THESE PESTICIDES NOT ONLY HARM THE FOOD CHAIN BUT ALSO THE SOIL AND DESTROY THE NUTRIENTS OF THE PLANTS.INDUSTRIAL WASTE:THESE NON BIODEGRADEABLE WASTES ARE GENERATEDBY INDUSTRIES WHICH CAN CONTAIN HARMFUL CHEMICALS WHICH CAN POLLUTE THE SOIL IF THESE WASTES ARE NOT DISPOSED PROPERLY THEY CAN CAUSE SERIOUS THREAT TO THE ENVIRONMENT .

STRATEGIES TO CONTROL ENVIRONMENTAL POLLUTION

WASTE MANAGEMENT:SOLID WASTE IS NOT ONLY WASTE WHICH YOU SEE IN YOUR HOUSEHOLD GARBAGE BOX.BESIDES HOUSEHOLD DISCARDS,THERE ARE MEDICAL,AGRICULTURAL,INDUSTRIAL AND MINING WASTES.THE IMPROPER DISPOSAL OF WASTES IS ONE OF THE MAJOR CAUSES OF ENVIRONMENTAL DEGRADATION.THERFORE THE MANAGEMENT OF THESE WASTES IS ONE OF THE UTMOST IMPORTANCE COLLECTION AND DISPOSAL:IT IS VERY IMPORTANT TO DISPOSE OUR WSTES CAREFULLY.IF THE WASTES ARE NOT DISPOSED PROPERLY IN THE GARBAGE BINS IT FINDS ITS WAY TO THE SEWERS.OTHER NON BIODEGRADEABLE WASTES CAN ALSO CHOKE ANIMALS AND CAN COST THEIR LIVES ALSO. THEREFORE WE SHOULD DISPOSE THE WASTE PROPERLY.THE POOR MANAGEMENT CAUSES HEALTH PROBLEMS LEADING TO EPIDEMICS DUE TO CONTAMINATION OF GROUND WATER.IT IS SPECIALLY HAZARDOUS FOR RAG PICKERS AS THEY ARE IN DIRECT CONTACT WITH THESE WASTE DISPOSALS.

GREEN CHEMISTRYGREEN CHEMISTRY IS WAY OF THINKING AND IS ABOUT THE WAY OF UTILISING THE EXISTING KNOWLEDGE AND PRINCIPLES OF CHEMISTRY AND OTHER SCIENCES TO REDUCE THE ADVERSE IMPACT ON ENVIRONMENT.GREEN CHEMISTRY IS A

PRODUCTION PROCESS THAT WOULD BRING ABOUT MINIMUM POLLUTION OR

DETERIORATION TO THE ENVIRONMENT. THE BYPRODUCTS GENERATED DURING THE PROCESS IF NOT USED GAINFULLY ADD TO THE ENVIRONMENTAL POLLUTION SUCH PROCESSES ARE NOT ONLY UNFRIENDLY BUT ALSO COST INEFFECTIVE.THE WASTE GENERATION AND ITS DISPOSAL BOTH ARE ECONOMICALY ONSOUND.UTILISATION OF EXISTING KNOWLEDGE BASE FOR REDUCING THE CHEMICAL HAZARDS ALONG WITH THE DEVELOPMENTAL ACYIVITIES IS THE

FOUNDATION OF GREEN CHEMISTRY .

GREEN CHEMISTRY IN DAY TO DAY LIFE

DRY CLEANING OF CLOTHES:TETRA CHLROROTHENE WAS EARLIER USED AS SOLVENT FOR DRY CLEANING.THE COMPOUND CONTAMINATES THE GROUND WATER AND ALSO A SUSPECTED CARCINOGEN.THE PROCESS USING THIS COMPOUND IS NOW BEING REPLACED BY A PROCESS WHERE LIQUEFIED CO2 WITH SUITABLE DETERGENT IS USED.REPLACEMENT OF HALOGENTAED SOLVENT BY LIQUID CO2 WILL RESULT IN LESS HARM TO GROUND WATER.THESE DAYS HYDROGEN PEROXIDE IS USED FOR THE PURPOSE OF BLEACHING CLOTHES IN THE PROCESS IN LAUNDARY WGHICH GIVES BETTER RESULTS AND MAKES USE OF LESSER AMOUNT OF WATER.BLEACHING OF PAPER:

CHLORINE GAS WAS USED EARLIER FOR BLEACHING PAPER.THESE DAYS HYDROGEN PERIOXIDE WITH SUITABLE CATALYST WHICH PROMOTES THE BLEACHING ACTION OF HYDROGEN PERIOXIDESYNTHESIS OF CHEMICALS:

ETHANAL IS NOW COMERCIALLY PREPARED BY ONE STEP OXIDATION OF ETHENE IN THE PRESENCE OF IONIC CATALYST IN AQUEOS MEDIUM WITH A YIELD OF 90%

THANK YOU

BY HUDA IRFAN DHABI11-C