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Environmental Chemistry. Section 3: Transport of Materials Through Air, Soil, and Water. 1) Transport in Air. There are 3 stages of transport of substances in air: Release of the chemical at the _______
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Section 3: Transport of Materials Through Air, Soil, and Water
1) Transport in Air There are 3 stages of transport of substances in air: • Release of the chemical at the _______ • ______________ of the chemical in the atmosphere (the chemicals scatter in all directions) • _____________ of the chemical in soil or water
The direction and distance that airborne chemicals travel are determined by various factors including: • pollutant’s ____________ • wind _________ • _____________ of prevailing winds
QUICKLAB Environmental Transport Read pg. 238 and complete Questions #2-4
2) Transport in Groundwater Water that soaks into soil moves through the following two zones: • B is the _______ zone where there is both air and water between the soil grains. • A is the second zone where all the spaces are filled with water. This water is called _____________ • Y – the top of the groundwater zone is called the ____________
Groundwater • Can move sideways, up and down • Can move ________ (1m/year) or ______ (1m/day) – still much slower than rivers • Due to its slow movement, __________ cannot be quickly dispersed and may build up over time • All homes and schools that use a well are drinking and washing in __________
Groundwater The number and connection of pores affect how ______ groundwater moves Pores: tiny spaces between soil grains Permeable soil: one with ___________ pores which allows water to flow easily
Groundwater contamination Use pg. 239 to fill in the following table
3) Transport in Surface Water • A substance that _________ easily in water may be carried away and dispersed by the water. • Some substances do not dissolve easily and they may become attached to solids such as soil grains – they will _______ and become concentrated closer to the source. • Communities that get their drinking water from rivers, lakes or reservoirs need to be careful about ____________ their water sources from contamination
4) Transport in Soil Water landing on soil does four things: • Some ___________ • Some soaks into the soil and is taken up by plants • Some runs onto the street or into a __________ • Some soaks through the soil and moves downward. This water may dissolve substances. This liquid is referred to as ____________
Assignment • Check & Reflect p.242 #1-9 • Work on Section 3 Vocabulary
3.2: Changing the Concentration of Harmful Chemicals in the Environment • The concentration of pollutants in the environment can be changed by dispersion, dilution, and biodegradation • ____________ is the scattering of substance away from its source • Spreading ___________ on your lawn is an example of dispersion
___________ reduces the concentration of a pollutant by mixing the polluting substance with large quantities of air or water For example, if you place one drop of bleach into a sink full of water, the molecules of bleach will mix with the molecules of water, and bleach will be diluted.
Dispersion and dilution may not leave an area clean enough to meet ____________ standards for clean water or air. • Dilution or dispersion combined with another clean-up process, such as ______________, may be more effective
___________ is the breakdown of materials by organisms such as earthworms, bacteria, and fungi (“bio” = living things; “degrade” = break up) • Micro-organisms such as bacteria are important in the biodegredation of pollutants • Some bacteria use oxygen for the process of __________ biodegredation while others don’t use oxygen for _____________ biodegredation • Bacteria that are anaerobic thrive deep in _______ sites where there is very little oxygen
The rate of biodegradation can be affected by six factors: • ____________ • Soil moisture • ___________ • Oxygen supply • ____________ availability • Planting vegetation
Example of biodegradation A site in Sarnia, Ontario was contaminated with an organic chemical called ethylbenzene. Approximately 400 tonnes of clay soil were dug up and placed in piles, and micro-organisms were added to the piles of soil. Within five months, concentrations of ethylbenzene dropped from 434 ppm to 25 ppm
Phytoremediation Eg: _______________ were used to remove radioactive substances from groundwater at Chernobyl Clean up of the environment using ________ “Phyto” means plant and “remediation” means to correction or cure Plants have been used to clean up metals, hydrocarbons and other chemicals
Photolysis • Breakdown of compounds by _________ • “Photo” means light; “lysis” means break down • Example: _________________ plastic • Ordinary plastic takes hundreds of years to break down • Photodegradable plastic is made of chemicals that react with sunlight and within three __________ break down into a fine powder that is easier to dispose of • Will not work if buried – why not??
Environmentally friendly solutions Hi-Cone carriers become brittle and break down into small pieces in sunlight. Depending on the season, carriers may break down as quickly as three to four weeks. Ring carriers are lighter than water; therefore, they will float. Since there are no by-products in our carriers, there is nothing to leach out into the water.
3.3: Biomagnification • Biomagnification is the ____________ in concentration of a chemical or element as it moves up the food chain • Mercury is a common element that biomagnifies • Mercury is found in waste fluids or the air and ends up in water systems • Mercury then travels up through the ___________ and increases in concentration
Legacy of an Oil Spill Read pg. 250-251 prior to the video
3.4: Hazardous Household Chemicals • Hazardous household chemicals include: • Household cleaners • Personal hygiene products • Pet-care products • Paint and paint products • Pesticides and fertilizers • Automotive fluids
Storage of Hazardous Chemicals • Always read the labels and pay attention to the ________ labels if there are any • Refer to MSDS documents for important information about handling • Leave all products in their __________ containers with the label intact • Be sure all containers are in good condition and have secure lids • Store corrosive, flammable, reactive and poisonous products on ___________ shelves or in separate locations • Place products in their storage areas so that they can’t fall over • Safely discard hazardous substances
Disposal of Hazardous Chemicals • Never pour hazardous wastes down the drain or into ______ • Never throw them in the __________ • Hazardous wastes poured down a drain go into _______ sewer systems or septic tanks • Take hazardous chemicals to __________ sites for proper disposal • Improper disposal can contribute to contamination of drinking water, soil, and even air
Assignment • Pg. 247 #1-7 • Section 3 Review p.260 #1,2,5,7,9 • Unit Review p.266 #2-15, 20-23, 25