Terms appearing in boldface italics on the other pages of this WebQuest are included in this glossary. A blue navigation table is provided after each glossary entry, with links to help you return to your previous location in the WebQuest.

The technical term for acid rain. Acid deposition includes the removal of acids from the atmosphere by rain, snow, fog, and by dry process such as settling by gravity.

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A substance that has an abundance of hydrogen ions, causing its pH to be less than 7.

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The quantity of acid in a substance, usually expressed as a pH.

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A type of meteorological chart that shows the pathway of air moving through the atmosphere.

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A substance that has fewer hydrogen ions, causing its pH to be greater than 7. This is the same as basic.

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A type of meteorological chart illustrating the pathway of air moving toward a particular location, called a receptor. Back trajectory charts are useful for finding the sources of pollution, dust or other material carried by the air. (Same as backward trajectory.)

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A substance that has fewer hydrogen ions, causing its pH to be greater than 7. This is the same as alkaline.

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A weak acid formed when carbon dioxide combines with water.

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The scientific study of matter, its properties, and interactions with other matter and with energy.

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The removal of pollution from the atmosphere. Wet deposition is removal by precipitation, dry deposition is removal without precipitation.

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A community of living organisms and their surrounding environment.

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Decay; the process of dissolving or wearing or grinding something down.

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A type of meteorological chart illustrating the pathway of air moving away from a particular location, usually a source of pollution. Forward trajectory charts are useful for finding the downwind areas that may be affected by a release of pollution.

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A picture taken with a satellite camera that records infrared radiation, or heat. The image shows the location and altitude of clouds.

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A picture taken with a satellite camera that records infrared radiation, or heat. The image shows the location and altitude of clouds.

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A sedimentary rock consisting mainly of calcium. Limestone is highly susceptible to erosion by acid rain.

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Dr. Bravo	Ms. Alarcón	Dr. Sosa	Dr. Soto	Mr. Sanchez

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Dr. Bravo	Ms. Alarcón	Dr. Sosa	Dr. Soto	Mr. Sanchez

A strong acid formed in the atmosphere by chemical reactions with nitrogen dioxide.

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An intermediate chemical ingredient in the processes leading to the formation of nitric acid.

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An intermediate chemical ingredient in the processes leading to the formation of nitric acid.

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Nitrogen oxide and nitrogen dioxide, together referred to as NOx. Same as oxides of nitrogen.

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Nitrogen oxide and nitrogen dioxide, together referred to as NOx. Same as nitrogen oxides.

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The unit of acidity. Acidic substances have pH less than 7, and basic or alkaline substances have pH greater than 7.

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The number of people living within a certain area, such as a square mile.

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Water that falls out of the atmosphere, including snow, rain and mixed forms such as sleet and freezing rain.

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A major air pollutant originating mostly from the burning of fuels.

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A short-lived sulfur ion that quickly reacts with oxygen to form sulfuric acid.

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A strong acid formed in the atmosphere by chemical reactions with sulfur dioxide.

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Dr. Bravo	Ms. Alarcón	Dr. Sosa	Dr. Soto	Mr. Sanchez

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