REGIONAL AND GLOBAL ATMOSPHERIC ASSESSMENT # 4

PART I.   CALCULATION OF PERSONAL PRODUCTION OF SULFUR DIOXIDE

QUES. 1:  In 1985, the total coal burned in the U.S. was 843 million tons, the population is 250 million, therefore each person is responsible for burning how many tons of coal?


QUES.  2:  How many pounds of coal are in the tons of coal consumed per capita per year calculated in Ques. 1 (1 ton = 2000 lbs)?


QUES. 3:  How many pounds of sulfur are in the  coal  calculated in Ques. 2?  Use the 3 % sulfur by weight for Illinois coal.

QUES. 4.   Use eq. a);  How many moles of sulfur are used for the reaction?  Steps follow:
  
	a.  First find the atomic mass of sulfur from the periodic table for 1 mole of sulfur in pounds.  1 mole sulfur  =    ______lbs

     
	b.  Now find the  moles of sulfur in the pounds of sulfur from Ques. 3.

			ans. Ques. 3   x     1 mole S     =       _________ moles  S
						ans. a

QUES. 5:   Use eq. A:   If  ans. Ques. 4b _____ moles of sulfur are used, how many moles of sulfur dioxide are produced in this reaction?  Steps follow:
 
	a.  First what is the mole ratio?  ÒReadÓ the balance equation A above.
		1 mole S   =  ____ mole SO2  

	b.   ans. Ques. 4b    x      1 mole SO2        =   ___________ moles  SO2  
					ans. Ques. 5a



QUES. 6:  Use the answer to QUES. 5b - the moles of sulfur dioxide to calculate the pounds of sulfur dioxide produced by burning coal.
	a.  First find the atomic mass of sulfur dioxide from the periodic table for 1 mole of sulfur dioxide in pounds.  Add the atomic masses for 1 sulfur and 2 oxygen.

  	1 mole sulfur dioxide  =    ______lbs
     
	b.  Now find the  pounds of sulfur dioxide  in the moles of sulfur dioxide from Ques. 5b.
					ans. Ques. 5b   x     ans. 6a      =       _________ lbs SO2  
							      1 mole SO2  
  

QUES. 7:  The above calculation shows how many pounds of sulfur dioxide are produced by each citizen of the U.S. from the burning of  high sulfur coal with no pollution controls.  However, a modern coal fired plant is able to remove 70-95 % of the sulfur dioxide before it is emitted into the atmosphere.
	Use the ans. to Ques 6b and a figure of 30% sulfur dioxide actually emitted into the atmosphere to calculate how many pounds of sulfur dioxide enter the atmosphere for each citizen.


QUES. 8:   The sulfur dioxide in the atmosphere undergoes two more reactions to produce sulfuric acid which may become part of acid rain.  Balance equation B below. 

B.     SO2    +    O2    ====>    SO3
C.     SO3     +   H20   ====>    H2SO4

PART II.   PH OF RAIN AND OTHER NATURAL WATER SAMPLES

Procedure 2.  PH MEASUREMENT OF WATER SAMPLES.
1.  As soon as possible after collecting the sample, use both the wide range and narrow range pH paper to measure the pH of the sample and record the results in table form.
2.  Discuss any significant findings or insights about the pH of various samples.

1.  1995 Field pH

QUES. 9:  Which areas of the country have the lowest pH values recorded?  What is the lowest pH and its location?

2.  1995 SO4-2 Concentrations (mg/L)

QUES. 10:  a.  Which areas of the country have the highest concentration of sulfate ion values recorded?  What is the highest sulfate ion concentration and its location?

b.  Which areas of the country have the highest carbon dioxide emissions which in turn correlate with the presence of mostly coal fired power plants? 
      see:  http://www.epa.gov/acidrain/scorcard/co295.gif
 
c.  What is the correlation between the deposition concentration and the emission of sulfur dioxide?
     see:  http://www.epa.gov/acidrain/scorcard/so295.gif  
     from http://www.epa.gov/acidrain/scorcard/es1995.html      Emission Scorecard 1995


3.  1995 NO3-1 Concentrations (mg/L)

QUES. 11:  a.  Which areas of the country have the highest concentration of nitrate ion values recorded?  What is the highest nitrate ion concentration and its location?

b.  What is the correlation between the deposition concentration and the emission of nitrogen oxides?
     see:  http://www.epa.gov/acidrain/scorcard/nox95.gif

QUES. 12:  a.  What is the correlation of pH,  sulfate ions, and nitrate ions in terms of location and high or low values?


b.  Why is the pH lowest for the northeast part of the country?


4.  1995 Ca+2 Concentrations (mg/L)

QUES. 13:  Which areas of the country have the highest concentration of Ca+2 ion values recorded?  What is the highest calcium ion concentration and its location?  Possible reason for high values?  (Hint:   Consider possible types of soil associated with wind carried dust which may derived from limestone, calcium carbonate.)


5.  1995 Cl-1 Concentrations (mg/L)

QUES. 14:  Which areas of the country have the highest concentration of chloride ion values recorded?  What is the highest chloride ion concentration and its location?  Possible reason for high values?  (Hint:   Consider that salt may enter the atmosphere from wind blown ocean spray)

QUES.15:  a.  Analyze the three maps and draw conclusions about whether these results show less, more, or no change in percent concentrations from the predicted model behavior for i.e. are acid rain pollutants getting worse or better:
sulfur dioxide:  http://h2o.usgs.gov/public/pubs/acidrain/sulpct.gif
pH:  http://h2o.usgs.gov/public/pubs/acidrain/lphpct.gif
nitrogen oxides:  http://h2o.usgs.gov/public/pubs/acidrain/nitpct.gif

 b.  What has the general trend been in the sulfur dioxide emissions over the last 15 years?  http://www.epa.gov/acidrain/scorcard/so28095.gif 


PART III.  OZONE DEPLETION

QUES. 16:  First concentrate on the Antarctica, look at a series of images starting with January 1 and look at every other month for the whole year.  Which months show evidence of the Òozone holeÓ?  Try to refine the dates for the optimal duration of the ozone hole.  Try some dates that are about 15 days apart.  When does the ozone hole begin and end?

     TOMS:     http://jwocky.gsfc.nasa.gov/eptoms/ep.html
	EARTH PROBE TOMS HOME Page.  

QUES. 17:  Give the approximate date and lowest concentration of ozone, in Dobson units, observed.

QUES. 18:  Is the distribution of ozone uniform over the surface of the globe during most times of the year such as during the summer months?  Comment on the ozone concentration levels near the equator, in the mid latitudes (North America/Europe) and polar regions.   Explain your observations. 

QUES. 19:   Is there any evidence of a similar ozone hole around the north polar region?  Look particularly at dates in Feb., Mar., and April. 
 
QUES. 20:  a.  Examine the ozone and reactive chlorine versus latitude graph below.  What is most striking about the relationships shown on the graph?  As the latitude increases (getting closer to the South Pole) the ozone concentration _________ while the chlorine concentration __________.

     The inactive forms of chlorine in hydrochloric acid and chlorine nitrate can react with ice crystals and nitric acid trihydrate crystals in very high cold clouds in the stratosphere over Antarctica.  This reaction on the surface produces diatomic chlorine molecule and nitric acid, which quickly dissociate into chlorine atoms in the sunlight of the Antarctic spring.  The reactive chlorine atoms start a cycle of destruction of ozone.  Chlorine atoms react with ozone to make chlorine monoxide molecules and oxygen molecules.  Chlorine monoxide reacts with atomic oxygen to make diatomic oxygen and reactive chlorine atoms to cycle over again.  Since there are few gaseous water molecules and virtually no nitrogen dioxide molecules to react with and inactivate the chlorine, the reactive chlorine builds up as chlorine monoxide.

b.  What is the series of chemical reactions which would explain the graph data?