Practice Quiz Study Guide
Composition of the atmosphere (10 - 15 pts). The five most abundant gases in the atmosphere (listed here in alphabetical order): argon (Ar), carbon dioxide (CO2), nitrogen (N2), oxygen (O2), and water vapor (H2O) (you should know approximate concentrations of all but CO2). Greenhouse gases: water vapor (H2O), carbon dioxide (CO2) and others. What do they do?  What weather variable is commonly used to measure atmospheric water vapor content?   Typical values of that variable in Tucson during the year?

Atmospheric evolution (5 - 10 pts). About how old is the earth? What was the earth's first atmosphere composed of?  Where is our present atmosphere thought to have come from? What are the three most abundant gases emitted by volcanoes? What important atmospheric constituent in our present atmosphere did not come from volcanoes? What is the principal source of that gas?  Stromatolites, cyanobacteria, banded iron formation.

Air pollution (0 pts). Primary and secondary pollutants. Air Quality Index (AQI). A pollutant is considered unhealthy when the AQI exceeds what value?

Carbon monoxide (CO) (10 pts). Toxic, colorless, odorless. Most abundant pollutant. What produces most of the CO in Tucson air? Incomplete combustion (what would complete combustion produce). Oxygenated fuels and catalytic converters.  Early morning and wintertime pollutant. What is a surface radiation inversion layer, when do they form? Stable and unstable atmospheric conditions.  Would a surface inversion layer act to concentrate or disperse CO?  CO is a serious indoor hazard.

Scattering of Light (0 - 5 pts).   Cloud droplets and ice crystals in clouds, particles, and air molecules all scatter ("splatter") light.  How do air molecules scatter light differently than cloud droplets or particulates?

Tropospheric ozone and Stratospheric Ozone (O3) (20 pts). Ozone aggravates existing respiratory diseases, is harmful to plant life, and damages materials such as rubber. Ozone is a secondary pollutant and is a key component of photochemical smog (also known as Los Angeles-type smog). To produce smog, ozone reacts with hydrocarbons. Peak ozone and photochemical smog concentrations occur on summer afternoons.

Ozone layer.  What beneficial role does it play?  Natural formation of stratospheric ozone.  CFCs destroy stratospheric ozone.

Sulfur dioxide (SO2) (5 pts). Toxic and aggravates existing respiratory diseases. The world's first pollutant. Natural and manmade sources. Involved in some of the world's worst air pollution disasters: Great London Smog of 1952, Donora (Pennsylvania) 1948. The word smog was first used to describe the combination of sulfurous smoke + fog; the term London-type smog is now used.  Reacts in clouds to form acid rain.  What gas was used in the acid rain demonstration in class?

Particulate Matter (PM) (5 pts).  Small particles (generally less than 10 micrometers) that are inhaled into the lungs and sometimes enter the bloodstream.  Sources of PM.  PM is a health concern and also affects visiblity.  How are PM and gaseous pollutants most effectively removed  from the atmosphere?

Sample questions ( from the online example quizzes )
Practice Quiz: 1, 3, 4-7, 9, 12, 13, 16a, 20, EC1        Quiz #1: 1, 2, 4a       Final Exam: 2, 20(2nd part)
 
Mass, weight, density, and pressure (15 - 20 pts).  Mass is the amount of a particular substance. On the earth gravity pulls downward on a mass producing weight. Pressure at any level in the atmosphere is a measure of the weight of the air above (this is one way of thinking about and understanding pressure). Pressure is defined as force divided by area and acts like a force (a force that pushes upward, downward, and sideways). Common pressure units and typical sea level pressure values.   What instrument is used to measure air pressure? About when was it invented?
Pressure and air density (density = mass divided by volume) both decrease with increasing altitude (you should be able to explain why). What relationship is there between the rate of pressure decrease and air density (i.e. does pressure decrease most rapidly in high or low density air)?

Sample questions
Practice Quiz: 15, EC2, EC3     Quiz #1:  3, 17a&b          Final Exam: 6, 11

Ideal Gas Law (10 - 15 pts).  This is a microscopic explanation of air pressure.  Two equations

P = N k T / V     &     P = ρ R T

N is the number of air molecules in a volume V, T is temperature and ρ is density.  R and k are both constants (you can pretty much ignore them).  You should be able to determine what will happen to the pressure in a rigid container or something flexible like a balloon if you change the variables in the equation above.  What variables could you change together in such a way that the pressure would stay constant?  Charles' Law.  In the atmosphere why is warm air normally low density air and cold air normally high density air?

Upward and downward forces (5 pts).  Vertical forces acting on air parcels (the strength of one of the forces depends on the air inside the parcel, the other on the air outside the parcel). These two forces are usually in balance. What happens to the balance when you warm or cool a parcel of air?  Basically you should be able to explain why a balloon of hot low density air rises and a balloon of cold high density air sinks.

 Reviews
Mon., Feb. 17
 4:30 - 5:30 pm Haury (Anthropology) 129
Tue., Feb. 18 4:00 - 5:00 pm
 Haury (Anthropology) 129