Environmental Chemistry Part Three

Question 1

What is Carbon Dioxide?

Answer 1

It is a greenhouse gas, naturally released by humans breathing, driving vehicles, combusting materials.

Question 2

What is global warming?

Answer 2

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.

Question 3

What is the ozone layer?

Answer 3

Protects us from UV rays, but has become thinner causing the rays to reach the surface. (results in skin cancer, cataracts, death of plankton)

Question 4

What causes the ozone layer to break down?

Answer 4

Chlorofluorocarbons (CFCs). They are broken down by the UV into chlorine that break up the Ozone into O2.

Question 5

Transport through air?

Answer 5

1. Release of chemical at source.
2. Dispersion of chemical into atmosphere
3. desposition of chemical into soil or water
   (dispersion depends on wind speed, direction, precipitation, properties of pollutant)

Question 6

Transport in ground water?

Answer 6

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

Question 7

Transport in surface water?

Answer 7

• Many sources possible
• chemicals don’t easily dissolve so they can become concentrated
• may attach on soil particles,sink, and build up

Question 8

Transport in Soil?

Answer 8

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

Question 9

What is dispersion?

Answer 9

Scattering of substance away from its source.

Question 10

What is dilution?

Answer 10

Mixes the pollutant with water or air; reduction of concentration.

Question 11

What is Biodegradation?

Answer 11

Worms, fungi, bacteria breakdown substances. (affected by temperature, moisture, acidity, oxygen levels, nutrients)

Question 12

Types of bacteria?

Answer 12

Aerobic- oxygen needed for breakdown

Anaerobic- oxygen not needed for breakdown

Question 13

What is phytormediation?

Answer 13

Using plants to reduce the concentration of chemicals in soil or groundwater.

Question 14

What is photolysis?

Answer 14

Breakdown of a substance due to the exposure of light.

Question 15

What is bioreactor technology?

Answer 15

Technology designed to speed up decomposition of organic wastes.

Question 16

What is Biomagnification?

Answer 16

Increase in concentration of a chemical as it moves up a food chain.