Science in Action Notes_ Environmental Chemistry (2

Science in Action Notes_ Environmental Chemistry (2 -...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1/30/12 Science in Action Notes: Environmental Chemistry (2.0) Science in Action Notes: Environmental Chemistry (2.0) Print 2.0 The quantit of chemicals in the environment can be monitored Monitoring keeps track of something for a specific purpose. 2.1 ? M onitoring Wate r Qualit Clarity may be one indicator, but clear water does not indicate what chemicals are present. Water Quality is determined using chemical and biological indicators according to what the water is going to be used for. The re are five cate gorie s of wate r us e : ? human drinking water ? recreation ? livestock drinking water ? irrigation ? protection of aquatic life Biological Indicators M icrobiological Indicators Microscopic organisms (bacteria) can cause serious health problems if they are present in sufficient numbers. Samples are taken to identify their presence to avoid contamination of the water supply. Aquatic Inve rte brate Ide ntification: (s ia p.214) Species of aquatic organisms (invertebrates ? animals without a backbone) require certain amounts of oxygen in the water to survive Aquatic Environme nts The place where aquatic organisms live can vary, depending on the pH level and the amount of dissolved oxygen present. ? there will likely be no fish in water that has a pH below 5.0 ... worms and midge larva thrive in polluted water, as they require only small amounts of dissolved oxygen for survival Che mical Factors That Affe ct Organis ms Chemical indicators of water quality include: dissolved oxygen, acidity, heavy metals, nitrogen, phosphorus, pesticides, salts ? such as sodium chloride and magnesium sulfate. M e as uring Che micals in the Environme nt The concentrations of chemical indicators is usually measured in /209-science-in-action-notes-environmental-chemistry-20?tm 1/5 1/30/12 Science in Action Notes: Environmental Chemistry (2.0) Mea i g Che ica i he E i O e a e ii ea ha e i f a e e e (SKILL P ac ice ? Pa e Mi i ? SIA . 217) I e iga i g Pa e ii e che ica ca be f di e ii i f i. ? Ac i i Lab Dis s olve d O ge n - Abi ic fac - a e e e a e, a e f f ( b e ce), b ac e i he a e , i d, a fh he i b a e a , - Bi ic fac be f ga i ig ge M ga i eed 5 i ig a e Li e (5 f e gi e a e a i e idea f he a f di ea a high e e ( i e 8 e) f di (be 5 ) f di ed ge . ) f di ed ge i e. The di e i f ecie ed ge e e . A a ge be f diffe e ecie ed ge , he ea a fe ecie i dica e a ee Phos phorus and Nitroge n Conte nt Ph ha e a d Ni a e f e e e he a e b e age a d ff ? The i c ea e he g h f a gae a d eed i he a e . Thi he i c ea e he f d f bac e ia, hich dec e he a , a he die. The e e ce f ea d e bac e ia e he a ai ab e f di ed ge a d a f he a a ic ga i die a a e . pH Te s ting ( ee e f Sec i 1) Acid Rain & Acid Shock S f a d i ge ide e i ed f i d ie ( ch a e e ) c bi e i h a e a i he ai d ce f ic a d i ic acid. The e a he fa he g d a acid ai ( i h a H e ha a ai - hich i ab 5.6) ... ca e che ica cha ge i ... e a d ee g h ... i ga i i ae& ... c de e ed e a ... b ea d ea d i ... eache ic che ica f he i ed ce i fe i i ea face e e he i Acidi i ea ed he H ca e i h 7.0 bei g e a a d a hi g be 7 i acidic. A dec ea e f e i i dica e he acidi ha bee i ied b a fac f 10. Pe i d f e e e acidi ( i e i he i g he he acid e a d he acidic a e e e he a e a ) a e ca ed acid h c . Pe s ticide s S e i ec ha e bec e e icide- e i a a d , e e icide ha e be de e ed. Whe he e che ica e ai i he e i e , a i i c ea ed. Se e a e icide i ed ge he ca ha e a c ai e /209-science-in-action-notes-environmental-chemistry-20?tm 2/5 1/30/12 Science in Action Notes: Environmental Chemistry (2.0) effec and become e o ic. A o ic b ance i poi ono . M e as uring To icit To in , o poi on a e o gani m. b ance ha p od ce e io heal h p oblem , o dea h hen in od ced in o an Scien i mea e o in in LD50 amo n . Table - h p:// e . l ane /Biolog Page /L/LD50.h ml LD and fo ?Le hal Do e? and 50 ep e en 50% of he he pecified do e, all a once. bjec g o p ha ill die if he a e gi en he He av M e tals Hea me al ha e a den i of 5g/cm3 o mo e. E ample incl de: me c , coppe , lead, inc, cadmi m and nickel. The e me al occ na all and a e al o p oce ed in o a ide a ie of p od c . Hea me al can be o ic o a ide ange of o gani m , o concen a ion a e con an l moni o ed. Hea me al can en e he a e ppl b he ac ion of acid ain and imp ope olid a e di po al ( hich can leach hea me al in o he g o nd a e ). Hea me al a e e peciall o ic o child en ca e abno mal de elopmen , b ain damage o e en dea h. Sus pe nde d Solids - T bidi - nplea an appea ance - block nligh - dec ea e o gen p od c ion Te ing: U e he fil a ion me hod o epa a e he ample in o e id e and fil a e Pho pha e : n ien ha enhance g o h of plan (e ce pho pha e im la e he g o h of algae and eed ). Dio in : chemical fo nd in ce ain pe icide and ind ial a e can ca e e e e illne and po ibl bi h defec . Noi e Poll ion: can ca e hea ing lo and o he damage o li ing o gani m . The mal Poll ion: can elimina e pecie nable o ole a e he inc ea e in empe a e 2.2 ? M onitoring Air Qualit /209-science-in-action-notes-environmental-chemistry-20?tm 3/5 1/30/12 Science in Action Notes: Environmental Chemistry (2.0) A : . M obile Air M onitoring Laborator :// 3. Sulfur Dio ide S D ( SO2( ) ) ../ // / ( . ). I .I 99%. T .S ? Nitroge n O ide s N O ( NO ( ) ) .V SIA . 226) NO . NO2 N Carbon M ono ide C , O . (S .I .M , , ( , , ) .I , , , , C . . Ground-Le ve l O one O ( O3( ) ) , , 3 - , .G .I , - , (VOC? ), .F . 2.3 M onitoring The Atmos phe re C .O /209-science-in-action-notes-environmental-chemistry-20?tm , . 4/5 1/30/12 Science in Action Notes: Environmental Chemistry (2.0) Carbon Dio ide As A Gre e nhous e Gas Carbon dioxide occurs naturally in the environment, but increasing amounts that are being produced by various human activities is creating a concern globally. The increasing population and increasing use of fossil fuels is creating some issues. The Gre e nhous e Effe ct The Greenhouse Effect is a naturally occurring event, the result of greenhouse gases (water vapor, carbon dioxide, and other gases) trapping some of the outgoing energy - retaining heat in a way somewhat similar to the glass panels of a greenhouse ? helping to maintain the Earth's average surface temperature of 15 C. The Enhance d Gre e nhous e Effe ct Many scientists support the theory that the enhanced greenhouse effect is causing temperatures to increase around the world. Human activities ? essentially, the burning of fossils fuels is the primary reason. Monitoring stations are set up to record the higher levels and governments are trying to find ways to reduce the emissions of carbon dioxide which is fueling this enhanced greenhouse effect and depleting the ozone layer. Global Warming It is not just human activities that are contributing to global warming, but volcanoes and forest fires are also part of the cause. The questions remain ? What should be done? ? or, Can we do anything about it at all? The O one La e r Ground- level ozone can have dangerous effects. Atmospheric ozone is the chemical that occurs high in the atmosphere where it maintains a shield around the Earth protecting everyone from harmful UV radiation from the Sun. The ozone layer is a natural formation 15 to 50 kilometers above us. Since the late 1970?s Scientists who have been monitoring this protective layer, have noticed that it is becoming thinner. They have also discovered ?holes? in the layer. This results in more UV radiation getting through to the surface of the Earth and increasing the likelihood of more organisms getting skin cancer and cataracts. It is also affecting the plankton population ? which is an important food supply for many animals. The Role of Chlorofluorocarbons The thinning of the atmosphere is caused by our use of chlorofluorocarbons ( CFC?s ). These chemicals eventually get into the upper atmosphere where they are broken down into elements like chlorine ? which destroys ozone. (1 chlorine atom can destroy 100, 000 ozone molecules. Many countries have signed agreements to reduce their use of these chemicals. /209-science-in-action-notes-environmental-chemistry-20?tm 5/5 ...
View Full Document

Ask a homework question - tutors are online