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2nd P. Science Quiz

Humidity The moisture content of air
Absolute humidity The mass of water vapor contained in a certain volume of air
Relative humidity The ratio of the mass of water vapor in the air at a given temperature to the maximum mass of water vapor the air could hold at that temperature expressed as a percentage
Greenhouse effect The process by which certain gases(principally water vapor, CO2, and methane) trap heat that radiates from the earth
% nitrogen in dry air 78%
% oxygen in dry air 21%
% other in dry air 1%
Parts per million The number of molecules(or atoms)of a substance in a mixture for every 1 million molecules in that mixture
% nitrogen in exhaled air 75%
% oxygen in exhaled air 16%
% CO2 in exhaled air 4%
% water vapor in exhaled air 4%
% other in exhaled air 1%
Created by: Raxiqwerty