Environmental Chemistry Part Three Flashcards
What is Carbon Dioxide?
It is a greenhouse gas, naturally released by humans breathing, driving vehicles, combusting materials.
What is global warming?
Increasing of temperature on Earth. It causes climate change, increase in storms/flooding, spread of disease. It is caused by natural processes (volcanoes) and human activity.
What is the ozone layer?
Protects us from UV rays, but has become thinner causing the rays to reach the surface. (results in skin cancer, cataracts, death of plankton)
What causes the ozone layer to break down?
Chlorofluorocarbons (CFCs). They are broken down by the UV into chlorine that break up the Ozone into O2.
Transport through air?
- Release of chemical at source.
- Dispersion of chemical into atmosphere
- desposition of chemical into soil or water
(dispersion depends on wind speed, direction, precipitation, properties of pollutant)
Transport in ground water?
ground water zone- all space between soil grains is filled with water.
a) top of this zone is the water table
b) groundwater moves slow compared to rivers so chemicals build up
c) If particles are tightly packed pores may not be connected meaning water can easily flow
Transport in surface water?
- Many sources possible
- chemicals don’t easily dissolve so they can become concentrated
- may attach on soil particles,sink, and build up
Transport in Soil?
Leachate- water moving through the soil that contains dissolved substances
a) Impermeable vs. Permeable (clay and sand)
b) Hydrocarbons
1. some dissolve in water
2.some coat soil particles and fill pores
What is dispersion?
Scattering of substance away from its source.
What is dilution?
Mixes the pollutant with water or air; reduction of concentration.
What is Biodegradation?
Worms, fungi, bacteria breakdown substances. (affected by temperature, moisture, acidity, oxygen levels, nutrients)
Types of bacteria?
Aerobic- oxygen needed for breakdown
Anaerobic- oxygen not needed for breakdown
What is phytormediation?
Using plants to reduce the concentration of chemicals in soil or groundwater.
What is photolysis?
Breakdown of a substance due to the exposure of light.
What is bioreactor technology?
Technology designed to speed up decomposition of organic wastes.