Final Exam Flashcards
How much of the worlds copper does Chile produce?
1/3
What are some of the copper companies?
BHP Billiton, Anglo American and Japan’s Sumitomo Corp
What are some of the jobs available at the US Borax mine?
Chemists, geologists, engineers, environmental scientists, milwright, electrician, equipment operators, senior quality advisor, business planning and analysis
What are four conflict minerals used in your cell phone
W (tungsten), Ta (tantalum), Au (gold), Sn (tin)
What does W (tungsten) do in your cell phone?
Makes your phone vibrate
What does Ta (tantalum) do in your cell phone?
Stores electricity for its battery
What does Au (gold) do in your cell phone?
Coats the wires
What does Sn (tin) do in your cell phone?
Solders the circuit board
What can precious metals be used for?
Military weapons,leading to war and human rights abuses
Where is Boron mined in the USA?
Boron California
Who mines boron in the USA?
Rio Tinto, US Borax
Where are the largest producers of boron?
Turkey and USA
What happens in the oxidation of Pyrite?
4FeS2 + 15O2 + 14H2O → 4Fe(OH)3 + 8SO4
2- + 16H+
Fe experiences a change in valence # from +2 in pyrite to +3 in ferric hydroxide.
The Fe is getting OXIDIZED, because it’s valence # increases
What is the most common oxidizing agent in enviornemnts in contact with the atomosphere?
Oxygen (O2)
How can the oxidation of pyrite be accelerated?
Mining or quarrying
What effect does Fe(OH)3 have?
It smothers organisms living on the stream bottom
How does Fe(OH)3 present?
Insoluble yellow-orange precipitate, also known as ferric hydroxide or yellow iron oxide.
Where can pyrite occur?
Shales that may be interbedded with coal seams, especially those that formed in marine coastal swamps.
What does strip mining of coal seams commonly cause?
Acidification of local surface waters because of the oxidation of pyrite by exposure to O2 and H2O.
What do Thiobacillus ferrooxidans do?
Catalyzes the oxidation of FeS2 to ferric ions and hydrogen ions. Convert insoluble metals to their soluble state.
What kind of bacteria is Thiobacillus ferrooxidans?
Acidophilic bacterium that obtains its energy through the oxidation of iron.
What are well known coal and metalliferous sulphide depoists around the world associated with?
Acid mine drainage
The pH scale is logarithmic.
This means that a small change
in pH represents a —— change in H+ concentration.
Large
What are solutions that resist changes to pH called?
Buffers
What do buffers do?
Act like sponges to absorb excess H+
Fluids in living organisms and seawater have strong ———–
capacity. In contrast, rainwater does not.
Buffereing
Where are acid soils commonly found?
Rainforests, jungles
Where are alkaline soils commonly found?
Deserts
The natural pH range for most plants is ——–, between ——–
acidic, 5.5 - 7.
True or false: sulfide minerals like pyrite that are underwater will not weather significantly. Explain!
True
What is the geological name for a rusty exposure of rock?
Gossan
What are some treatments for acid mine drainage?
- add a buffer material like limestone
- limit the area of exposed rock
- compacting acid-generating rock
- covering the rock with sealing layers
What common aspect do current aprroaches to AMD have?
They delay or
prevent oxidation
Physical barriers for AMD
Such as wet or dry cover have slowed sulfideoxidation in several studies; however, both wet and dry barriers
exhibit only short-term effectiveness. Wet cover is suitable atspecific sites where complete inundation is established, but thisapproach requires high maintenance costs. When using dry cover,plastic liners are expensive and rarely used for large volumes of waste.
Bactericides for AMD
can suppress oxidation, but are only effective on fresh tailings and short-lived, and do not serve as a permanent solution to AMD. In addition, application of bactericides may be toxic to aquatic organisms.
Chemical barriers for AMD
on sulfide surfaces (applying organic and/or inorganic coatings) are effective in preventing AMD. Among inorganic coatings, silica is the most promising, stable, acid-resistant and long lasting.
How long can the effects of AMD be present?
Hundreds, even thousands of
years
What health impacts is AMD reposbible for?
Physical, chemical, and biological degradation of stream habitat. It jeopardizes not only fish, but also the animals who feed on them.
What are some physical properties of gold
Soft, malleable, pounded thin, drawn out to make a thin wire, made into shapes, doesn’t rust or tarn
Gold is usually bonded to other metals such as?
Silver
What role does cyanide play in gold processing?
Cyanide helps extract the gold from the other metals, and leach it into the surrounding water
What temperature is the smelter?
1600 degrees C
What are impurities in the smelting process called?
Slag
Gold cyanidation is used in –% of gold production
90
Why is gold cyanization controversial?
The toxic nature of cyanide
Where was the Baia Mare cyanide spill?
Baia Mare, Romania
What were the effects of the Baia Mare cyanide spill
The polluted waters eventually reached the Tisza and then the Danube, killing large numbers of fish in Hungary and Romania. The spill has been called the worst environmental disaster in Europe since theChernobyl disaster
What is the toxicity of cyanide tpically ecpresses as?
The concentrationthat is lethal to 50% of the exposed population (LC50)
What is the LC50 of cyanide via inhalation?
LC50 for gaseous hydrogen cyanide is 100-300 parts per million. Inhalation of cyanide in this range results in death within 10-60 minutes.
What is the LC50 of cyanide via for ingestion?
LC50 for ingestion is 1-3 milligrams per kilogram of
body weight
What is the LC50 of cyanide via absorption through the eyes and skin?
LC50 is 100 milligrams per kilogram of body weight
How does cyanide effect the body?
Cyanide interferes with the cell’s ability to use oxygen, causing cellular suffocation. This leads to depression of the central nervous system and respiratory arrest.
How does Mercury get into the environment?
Mercury is a chemical element that can be found in small concentrations in many rocks and is the main component of the mineral cinnabar (HgS). Natural background levels can be detected in soils, air, and water around the world.
Mercury is present in gases emitted by volcanoes. Mining and industrial applications for the metal have increased significantly since the industrial revolution. Base metal smelting and gold mining both create mercury vapor, which is a potential hazard.
What thrtee industry sectors make up 2/3 of the totalUS mercury emissions?
medical waste incinerators, municipal waste combustors, and coal-fired power plants
Although cyanide is cheap, effective, and biodegradable (it degrades in sunlight), why has it been banned for gold extraction in the US states of Montana and Wisconsin, the Czech Republic, and Hungary
High toxicity
What are the three chemicakl forms of mercury?
Elemental
Inorganic
Organic
Elemental mercury
liquid metal
Inorganic mercury
Mercuric chloride
Mercuric sulfide (cinnabar)
Organic mercury
Methyl, ethyl, dimethyl mercury
Phenyl organic groups
How is mercury converted to methylmercury?
By bacteria in
sediments
What happens to methylmercury?
It biomagnifies in aquatic animals,
and the concentrations can increase by a million fold in animals at the top of the food chain
Where is methylmercury absored 100%?
Through the gastrointestinal tract and distributed through the body
What is the major source of organic mercury for humans?
Methylmercury
What is the formula for methylmercury?
[H3CHg]+
What are the health affects of mercury?
As a reproductive toxin and a potent neurotoxin, mercury affects the brain and the central nervous system.
Who is at greatest risk to mercury?
Pregnant women, women of childbearing age, and small children are at greatest risk because mercury can cross the placenta and cause irreparable neurological damage to the fetus
What is paresthesia
numbness of skin
What is ataxia
lack of coordination of muscle movements
What was the Irraq grain disaster?
A mass methylmercury poisoning incident that began in late 1971
What was grain treated with that caused the grain disaster?
A methylmercury fungicide
Where was the toxic grain imported to?
Imported into Iraq as seed grain from Mexico and the United States
What is Minamata disease?
A neurological syndrome caused by severe mercury poisoning
What are the symptoms of Minamata disease?
ataxia, numbness in the hands and feet, general muscle weakness, loss of peripheral vision, and damage to hearing and speech.
What was Minamata diseased caused by?
The release of methylmercury in the industrial wastewater from the Chisso Corporation’s chemical factory, which continued from 1932 to 1968. This highly toxic chemical accumulated in shellfish and fish in Minamata Bay, which, when eaten by the local population, resulted in mercury poisoning
Other than Japan where else did MInamata disease appear?
It severely affectedtwo First Nation communities (Grassy Narrows and Whitedog) in Northwestern Ontario following consumption of local fish contaminated with mercury, and one First Nation in Southern Ontario due to illegal disposal of industrial chemical waste
What percentage of the population in Japan showed signs of poisoning?
90%
What is dental amalgam?
A dental filling material used to fill cavities caused by tooth decay
What percentage of dental amalgam is elemental mercury by weight?
50%
What does a dental amalgam consist of?
A mixture of metals, consisting of liquid (elemental) mercury and a powdered alloy composed of silver, tin, and copper
What are dental amalgams also know as?
“silver fillings” because of their silver-like appearance
How do dentists make dental amalgam?
The dentist mixes the powdered alloy with the liquid mercury to form
an amalgam putty
Is the mercury in dental amalgam the same as the mercury in some types of fish?
NO! The form of mercury associated with dental amalgam is elemental mercury, which can slowly release mercury vapor. The form of
mercury found in fish is methylmercury, a type of organic mercury.
Mercury vapor is mainly absorbed by the _____
lungs
Methylmercury is mainly
absorbed through the ____
Digestive tract
Benefits of dental amalgam fillings?
Strong and long-lasting
Lest expensive
Risks of dental amalgam fillings?
Contain elemental mercury so it releases low levels of mercury in the form of a vapor that can be inhaled and absorbed by the lungs
Are dental amalgam fillings dangerous?
The FDA considers dental amalgam fillings safe for adults and children
ages 6 and above
Where was the deepwater horizon oil spill?
Gulf of Mexico near Mississippi Delta, U.S.
What was the estimated total dischrage of the deepwater horizon oil spill?
4.9 million barrels
What was the cause of the deepwater horizon oil spill?
Wellhead blowout
Causalities from the deepwater horizon oil spill?
11 killed 17 injured
Who was at fault for the deepwater horizon oil spill?
mostly BP, but also rig operator Transocean and contractor Halliburton. Blamed for gross negligence, a series of cost-cutting decisions and an inadequate safety system.
What are the health effects on wildlife from the deepwater horizon oil spill?
Extensive damage to marine and wildlife habitats and fishing and tourism industries was reported. Oil is embedded in the sand.
What animals does the video mention as a “poster animal” for the spill? The oil affects the animal at every stage of life.
Turtles
What are the main effects of oil on birds?
Can’t thermoregulate, spend all their time preening
What is meant by the term “baseline data”?
Data about the area prior to an event or disaster
What is Corexit?
chemical dispersant, sinks to sea floor
when mixed with oil. Dispute about
toxicity.
What is some physical evidence of the spill still found on beaches in the Gulf Coast?
oily sea foam, tar balls
What are some medical issues mentioned in this video about the Deepwater Horizon disaster, five years later?
chronic cough, skin rash, memory loss
What did the spill do to the real estate market?
Houses spend long time on market
Methods Used to Contain/Eliminate Oil
A massive response ensued to protect beaches, wetlands and estuaries from the spreading oil by utilizing:
a) skimmer ships
b) floating containment booms
c) controlled burns
d) oil-eating microbes
e) 1.84 million US gallons (7,000 m3) of oil dispersant (Corexit)
Containment booms
deployed, either to corral the oil or as barriers to protect marshes, mangroves, and shrimp/crab/oyster farms. Booms extend 18–48 inches above and below the water surface
How does Corexit work?
A mixture of emulsifiers and solvents that helps break oil into small droplets following an oil spill. Small droplets are easier to disperse throughout a water volume, and small droplets may be more readily biodegraded by microbes
Concerns with Corexit
Contains possible cancer-causing agents, hazardous toxins and endocrine-disrupting chemicals
Excessive exposure may cause central nervous system effects, nausea, vomiting, anesthetic or narcotic effects
How did the blowout occur?
high-pressure methane gas from the well expanded into the drilling riser and rose into the drilling rig, where it ignited and exploded, engulfing the platform.