unit 7 vocab

Air pollution The introduction of chemicals, particulate matter, or microorganisms into the atmosphere at concentrations high enough to harm plants, animals, and materials such as buildings, or to alter ecosystems.

Sulfur dioxide (SOz) A corrosive gas that comes primarily from combustion of fuels such as coal and oil, including diesel fuel from trucks.

Haze Reduced visibility.

Photochemical oxidant A class of air pollutants formed as a result of sunlight acting on chemical compounds such as nitrogen oxides and sulfur dioxide.

Smog A type of air pollution that is a mixture of oxidants and particulate matter.

Lead (Pb) A trace metal that occurs naturally in rocks and soils, is present in small concentrations in coal and oil and is a neurotoxin.

Hydrocarbons Pollutant compounds that contain carbon-hydrogen bonds, such as gasoline and other fossil fuels, lighter fluid, dry-cleaning fluid, oil-based paints, and perfumes.

Photochemical smog Smog that is dominated by oxidants such as ozone. Also known as Los Angeles-type smog; brown smog.

Sulfurous smog Smog dominated by sulfur dioxide, sulfate compounds, and particulate matter. Also known as London-type smog; gray smog; industrial smog.

Sublimate The process of converting from a solid to a gas or vapor.

Formaldehyde A naturally occurring compound that is used as a preservative and as an adhesive in plywood and carpeting.

Thermal inversion An atmospheric condition in which a relatively warm layer of air at mid-altitude covers a layer of cold, dense air below.

Inversion layer The layer of warm air that traps emissions in a thermal inversion.

PM,10 Particles smaller than 10 um are called Particulate Matter-10 and are not filtered out by the nose and throat and can be deposited deep within the respiratory tract.

PM 2.5 Particles of size 2.5 um and smaller can travel further within the respiratory tract and are of even greater health concern.

Indoor air pollutants Compounds that adversely affect the quality of air in buildings and structures.

Asbestos A long, thin, fibrous silicate mineral with insulating properties, which can cause cancer when inhaled.

Radon-222 A radioactive gas that occurs naturally from the decay of uranium and is an indoor air pollutant.

Sick building syndrome A buildup of toxic pollutants in weatherized spaces, such as newer buildings in the developed world.

Vapor recovery nozzle A device that prevents VOCs from escaping into the atmosphere while a person is fueling their vehicle.

Catalytic converter A device that uses chemicals to convert pollutants such as nitrogen oxide and carbon monoxide to nitrogen gas and carbon dioxide.

Scrubber A device that uses a combination of lime and or water to separate and remove particles from industrial exhaust streams.

Electrostatic precipitator A device that removes particulate matter by using an electrical charge to make particles coalesce so they can be removed from the exhaust stream.

ph The relative strength of acids and bases in a substance. It is a logarithmic scale, meaning that each number on the scale .represents a change by a factor of 10.

Noise pollution Unwanted sound that interferes with normal activities that is loud enough to cause health issues including hearing loss.

decibel A scale (db(A)) A logarithmic scale that measure both the loudness of sound and the frequency.

Acid A substance that contributes hydrogen ions to a solution.

Base A substance that contributes hydroxide ions to a solution.

Acid rain Precipitation high in sulfuric acid and nitric acid. Also known as acid deposition