Science Test Tomorrow!

Tomorrow wraps up Chapter 13- it has been a fast and furious chapter about the atmosphere. Remember, the studyguide is bonus this time, but the review is due tomorrow. You also have a math page due tomorrow, the General Review.

The science notes for the chapter are as follows:

Chapter 13 Notes

Section 1: The Air Around You

I. Importance of the Atmosphere
A. Weather- the condition of Earth’s atmosphere at a particular time and place
B. Atmosphere- layer of gases that surrounds the planet
1. Makes conditions on Earth suitable for living things
2. Contains oxygen and other gases
3. Traps energy from the sun to keep Earth warm
4. Protects from sun’s radiation
5. Prevents Earth from being hit by meteoroids
II. Composition of the Atmosphere
A. Nitrogen
B. Oxygen
1. Organisms use oxygen from the air
2. Ozone- form of oxygen that has 3 oxygen atoms in each molecule
C. Carbon dioxide
1. Plants must have CO2
2. Burned fuels give off CO2
D. Water vapor
1. Water in the form of a gas
2. Clouds form when water vapor condenses
E. Other gases
F. Particles of liquids and solids
1. Dust
2. Smoke
3. Salt
4. Other chemicals

Section 2: Air Quality

I. Air Pollution
A. Pollutants- harmful substances in the air, water, or soil
B. Most pollution is the result of burning fossil fuels such as coal, oil, gasoline, and diesel
II. Particles
A. Natural Sources
1. Water vapor
2. Salt
3. Mold and pollen
4. Dust, soot
5. Dust & ashes
B. Human Activities
1. Burning fuels releases soot
2. Soil particles
III. Smog
A. Particles in coal smoke combine with water droplets in air
B. Photochemical smog- The nitrogen oxides, hydrocarbons, and other air pollutants then react with one another in the presence of sunlight to form a mix of ozone and other chemicals
IV. Temperature Inversion
A. A layer of warm air prevents the rising air from escaping
B. Polluted air is trapped
C. Smog becomes more concentrated
V. Acid Rain
A. Forms when nitrogen oxides and sulfur oxides combine with water in the air to form nitric acid and sulfuric acid
B. Acid rain- rain that contains more acid than normal
VI. Improving Air quality
A. Filters on factories
B. Pollution control devices on cars

Sec. 3: Air Pressure

I. Properties of Air
A. Mass
B. Density- amount of mass in a given volume of air (mass/volume)
C. Pressure- the force pushing on an area or surface
II. Air pressure- the result of the weight of a column of air pushing down on an area
A. Barometer- an instrument used to measure changes in air pressure
1. Mercury barometer- consists of a glass tube open at the bottom end and partially filled with mercury
2. Aneroid barometer- an airtight metal chamber sensitive to changes in air pressure
B. Measured in millibars or inches of mercury
III. Increasing Altitude
A. Altitude- elevation, or distance above sea level
1. Air pressure decreases as altitude increases
2. As air pressure decreases, so does density

Sec. 4: Layers of the Atmosphere

I. Troposphere
A. Lowest layer of the Earth’s atmosphere
B. Conditions are more variable than in other layers
C. Where weather occurs
D. As altitude increases, temperature decreases
II. Stratosphere
A. Extends from the top of the troposphere to about 50 km above Earth
B. Upper stratosphere is warmer than lower stratosphere
C. Upper stratosphere contains ozone
III. Mesosphere
A. Marked by a drop in temperature
B. Middle layer of the atmosphere
C. Coldest part of the atmosphere, temps near -90C
D. Protects surface from being hit by most meteoroids
IV. Thermosphere
A. Outermost layer of the atmosphere
B. No definite outer limit
C. Very hot, up to 1800 C
D. No heat felt; not enough molecules
E. Layers
1. Ionosphere- lower layer of the thermosphere
a. Aurora borealis- northern lights
2. Exosphere- outer layer of the thermosphere where satellites orbit

Happy studying!