Topic 2 Science in Action 9 Environmental Chemistry

biological indicators

organisms that live in water to help determine water quality

parts per million

the measurement of the concentration of chemicals in a substance

acid rain

when the pH of precipitation drops below 5.6, it is considered what?

toxicity

describes how poisonous a substance is

LD50

amount of a substance that causes 50% of a group of test animals to die if they are given a specified dosage of the substance all at once

sulfur dioxide

a colorless gas. It is a major air pollutant that forms both smog and acid rain. It is formed through burning fuels such as coal, oil, and natural gas, and is then combined with oxygen. It has a very pungent and strong odor

scrubbers

industrial and electrical generating power plants use these to reduce sulfur dioxide emissions

carbon monoxide

a colorless, odorless gas produced mainly when substances are burned but are not combined with oxygen.

nitrogen oxides

It is a group of seven gases composed of nitrogen and oxygen. They are major air pollutants that form both smog and acid rain. It is formed mainly from combustion in vehicles and generating plants

carbon dioxide

a colorless, odorless, greenhouse gas produced by burning carbon and organic compounds, which are then combined with oxygen, and by breathing air out of the respiratory system.

ozone layer

It is a layer in the atmosphere that absorbs ultraviolet radiation from the sun. That will then protect organisms on Earth from damaging UV rays

greenhouse effect

radiant energy from the sun that is trapped from escaping the earth's atmosphere by a layer of gases

ground level ozone

a pollutant that is formed when reactions occur in the presence of heat and sunlight.

enhanced greenhouse effect

this occurs when greenhouse gas concentration in the atmosphere is too high, causing too much heat to be trapped and thus increasing the temperature on Earth