IB Chemistry Option 1

An air pollutant is described as any substance that that is normally present in air but in excess.

Carbon monoxide, nitrogen oxides, and sulfur dioxide are the three primary pollutants.

Secondary pollutants are substances formed from the reacction of primary pollutants with air particles.

Pollutant Natural Sources Anthropogenic Sources Health Effects Methods of Abatement

Carbon monoxide     Incomplete atmospheric oxidation of methane,

that was produced by anaerobic bacteria from decaying organic material.

    Incomplete combustion of fossil fuels used in internal combustion engines and coal fired electrical generating facilities.

   Blocks the ability of the hemoglobin to transport oxygen to the cells

   Use of catalytic converters on vehicles    Thermal exhaust reactors    Lean burning engines

Hydrocarbons and Volatile Organic Compounds (VOC’s)

    Trees and other plants emit hydrocarbons known as terpines

    Unburned or partially burned fuel escaping from engines.

    Evaporation of industrial solvents

   Fumes may be toxic or carcinogenic as in the case of benzene.

   Formation of secondary air pollutants such as PAN’s

   Use of catalytic converters to reduce emissions

   Controls on the use and disposal of organic solvents

Particulates     Soot ash, dust, asbestoes, sand, smoke, pollen, bacterial and fungal spores

    Burning fuels, especially coal and diesel

   Affects the lungs and the respiratory system causing emphysema, bronchitis, and lung cancer

   Sedimentation and    Electrostatic precipitation

Oxides of NitrogenNO and NO2

    Electrical storms     Biological processes

    High temperatures inside internal combustion engines cause a direct reaction between atmospheric nitrogen and oxygen

   Respiratory irritants    Recirculation of exhaust gases and the use of a catalytic converter

Oxides of SulfurSO2 and SO3

    Oxidation of hydrogen sulfides produced by decaying organic material, volcanoes

    Burning of sulfur containing coal by smelters and power plants

   Respiratory irritants

   Removal of sulfur from coal before combustion, use of scrubbers

Thermal exhaust reactors (CO), Lean-burn engines (CO), Catalytic Converters (CO), Coal Burning of sulfur dioxide by scrubbing with limestone , Electrostatic precipitation chambers to remove aggregated particles

If these pollutants are not removed from the air then Acid deposition can occur.

ACID RAIN The acids in the atmosphere may be transformed into gases

and salts before falling back to earth. (Dry Acid Deposition- Sulfur Dioxide)

Pure rainwater naturally contains dissolved CO2 in the form of carbonic acid and has pH of 5.65- Acid Rain is therefore described as having pH of less than that and is caused by the presence of oxides in sulfur and nitrogen present in the atmosphere.

Increased acidity in the soil depletes calcium, magnesium, ,and potassium that nourishes flora and fauna.

Reduction of magnesium can cause reduction in chlorophyll levels and therefore inhibit the plants from photosynthetic process – stunting growth, leaf loss…

Acid Rain also causes aluminum to runoff into the soil and can damage root so that water intake is low leading to plant death.

Aquatic life is highly sensitive to pH imbalance. Breathing in acidic air irritates the mucus membranes and increases the

risk of respiratory illness such as asthma, bronchitis, and emphysema. There is research that links poisonous ions in water to developing cases of Alzheimer’s Disease.

ACTIVITY--- BROCHUREList the main greenhouse gases and their

overall contribution to increased global warming.

List 4 effects of global warming and give an appropriate definition of global warming.

HOMEWORK- Article Review- Read an article of choice and write a review…summary of article, your opinion, and recommendation of article- INCLUDE ARTICLE WITH BROCHURE

http://video.google.com/videoplay?docid=6257664215421518968#

Global Warming Influences

It is difficult to prove direct links between greenhouse gas emissions and changes in weather patterns such as floods, hurricanes, and storms. However, the two most likely major effects are

Changes in agriculture and biodistribution as climate changes

Rising sea levels due to thermal expansion and the melting of polar caps and glaciers

Sulfue hexafluoride

Greenhouse trapping effect 22,200 times that of carbon dioxide.

However, it is present in the atmosphere only in small amounts, so does not contribute hugely to global warming but could bc it is now the insulating material in generators and carries toxic PCBs.

At a pressure of one atm and a temp of 20 degrees Celsius the max solubility of oxygen in water is 9 ppm. This value is small but VITAL bc most aquatic organisms require oxygen for aerobic respiration. The oxygen content in water should be no less than 6 ppm.

When organic matter decomposes aerobically in water is uses up DO. The biological oxygen demand is a measure of the DO (in ppm) required to decompose the organic matter in water biologicallly.

MEASUREMENT OF BOD LAB ACTIVITY

Measurement of BODWinkler MethodThe sample of water is saturated with oxygen so that

the initial concentration of DO is known.A measured volume of the sample is then incubated at

a fixed temp for 5 days while micro-organisms in the water oxidize the organic material

An excess of Manganese (II) salt is added and is oxidized to Manganese (IV)

Potassium Iodide is then added to form iodine.The iodine is then titrated with sodium thiosulateBy knowing the moles of iodine present, the amount of

oxygen present in the sample of water can be calculated.

Aerobic and Anaerobic DecompositionElement Aerobic Decay Anaerobic Decay

Draw a Picture depicting Eutrophication and explain what it is, how to reverse the process---all using a “catchy phrase”

Eutrophication

Life is NOT Good.

HOMEWORK:

1. What are different sources of water pollution?2. What is waste water treatment and draw a picture

or flow diagram of the primary treatments, secondary treatments, and tertiary treatments that are conducted on the water particles?

Landfill, open dumping, and ocean dumping GROUP A for advantages

L, O, O Group B for disadvantages

Incineration and Recycling GROUP B for advantages

I, R Group A for disadvantages

Research, Research, Research

1. Explain soil degradation and give examples of ways in which humans have contributed to soil contamination, etc…

2. Inquiry..If I were a farmer or first beginner gardener and I was losing my crops, what information could you give me to help maintain my soil so that I could have a successful garden?

3. page 348 (#2) answer by discussing storage and disposal of nuclear wastes.

4. What are the conditions needed for smog to occur? 5. Explain Thermal Pollution. 6. Describe 7 water pollutants. 7. What is the acid rain formula when acid rain hits rocks and

marble? 8. What is the cation exchange capacity?

Station Rotation

TEST- Next Thursday

DONE WITH OPTION #1