‘‘?:.?:.Acid RainAcid Rain

Neutral water has a pH of 7Neutral water has a pH of 7 Pure “pristine” rain has a pH of 5.6Pure “pristine” rain has a pH of 5.6 This is due to dissolved COThis is due to dissolved CO22 in the in the

rainwaterrainwater Rain which has a pH < 5.6 is acid Rain which has a pH < 5.6 is acid

rainrain

How is acid rain How is acid rain formed?formed?

How is acid rain How is acid rain formed?formed? Combustion of fossil fuels in power Combustion of fossil fuels in power

plantsplants Automotive engine emissionsAutomotive engine emissions Non-combustion sources such as metal Non-combustion sources such as metal

ore smelting plants, and industrial ore smelting plants, and industrial chemical processing plantschemical processing plants

LighteningLightening Volcanic eruptionsVolcanic eruptions Sea salt spraySea salt spray

What are the primary What are the primary sources of acid rain?sources of acid rain?

SO2

69.4

3.7

12.7

11.6

2.2

0

utilities transport Ind/Mfg. Process

Ind. Combustion Other Combustion Other

Nox

32.4

43

4.6

15.6

3.8

0.6

Buffers and Acid RainBuffers and Acid Rain

Acid Rain’s EffectsAcid Rain’s Effects

Acid rain leaches Acid rain leaches KK++, Ca, Ca2+2+, and Mg, and Mg2+2+ ions (essential ions (essential nutrients) from nutrients) from soilsoil

Acid rain Acid rain mobilizes Almobilizes Al3+3+ and and other toxic metalsother toxic metals

Concentration UnitsConcentration Units

% (Parts per % (Parts per hundred)hundred)

ppm (parts per ppm (parts per million) 1 in million) 1 in 1,000,000 or 1 in 1,000,000 or 1 in 101066

ppb (parts per ppb (parts per billion) 1 in billion) 1 in 1,000,000,000 or 1,000,000,000 or 1 in 101 in 1099

How many grams How many grams of NaCl are in of NaCl are in 25mL of a 0.1% 25mL of a 0.1% NaCl (w/v) NaCl NaCl (w/v) NaCl solution? solution? Assume the Assume the density of the density of the solution is 1g/mL.solution is 1g/mL.

I want to make 500mL of a 350 I want to make 500mL of a 350 ppm NaOH, how may grams of ppm NaOH, how may grams of NaOH do I need? Assume the NaOH do I need? Assume the density is 1g/mL.density is 1g/mL.

Concentration Units Concentration Units ExampleExample

The maximum allowed concentration of ozone in the The maximum allowed concentration of ozone in the troposphere (lower part of the atmosphere) before it troposphere (lower part of the atmosphere) before it starts to be unhealthy is 0.08ppm. If 100 liters of air starts to be unhealthy is 0.08ppm. If 100 liters of air were analyzed and found to contain 0.13g of ozone, is were analyzed and found to contain 0.13g of ozone, is the air over the safe limit? The density of air is the air over the safe limit? The density of air is 0.00125g/mL.0.00125g/mL.

The maximum allowed concentration of The maximum allowed concentration of ozone in the troposphere (lower part of the ozone in the troposphere (lower part of the atmosphere) before it starts to be unhealthy atmosphere) before it starts to be unhealthy is 0.08ppm. If 100 liters of air were is 0.08ppm. If 100 liters of air were analyzed and found to contain 0.13g of analyzed and found to contain 0.13g of ozone, is the air over the safe limit? The ozone, is the air over the safe limit? The density of air is 0.00125g/mL.density of air is 0.00125g/mL.

Concentration Unit Concentration Unit ExampleExample The maximum The maximum

allowed allowed concentration of Pb concentration of Pb in drinking water is in drinking water is 7.24 x 107.24 x 10-8-8M. In M. In Door County, WI, 5 Door County, WI, 5 liters of water was liters of water was analyzed for Pb and analyzed for Pb and found to contain found to contain 325325g. Is Door g. Is Door County in County in compliance?compliance?