Environmental Chemistry Flashcards
What are nutrients?
Chemicals that are used by the body for energy, growth, body building, and cell repair
What are sorbents?
Any substance that can absorb or capture oxides
What does organic mean?
Carbon-containing, produced in plants
What are the main organic nutrients?
Carbohydrates, vitamins, lipids, and proteins
What do vitamins do?
Help enzymes function. Examples are vitamin A which helps vision, Vitamin B helps cell division, Vitamin C forms connective tissue, vitamin E prevents heart attacks, and Vitamin K helps blood clot
What do carbohydrates do?
Provide immediate energy
What do lipids do?
Provide stored energy
What do proteins do?
Structural molecule of the body and helps chemical reactions
What are macrominerals and trace elements?
Macrominerals are elements that you need over 100 mg per day and trace elements are elements that you need under 100 mg per day
What do different elements do in the body?
See image 25
How do we get the nutrients we need?
Through other organisms such as plants and animals, due to a plant’s ability to concentrate nutrients very well
What does NPK stand for?
Nitrogen, phosphorus, and potassium, that benefit leaves, roots and seeds respectively
Why is fertilizer important?
It allows us to grow much Much MUCH more food
What are pesticides and what are the 3 types?
Something sprayed to prevent that area from being contaminated by pests and include insecticides, herbicides, and fungicides
What does DDT stand for?
Dichlorodiphenyltrichloroethane
What were the benefits of DDT?
It stopped millions of deaths from malaria, yellow fever, typhus etc., earning its inventor, Paul Hermann Muller a Nobel prize
What were the downsides of DDT?
It quickly spread into ecosystems, killing off many many many species through the food web, even causing mutations and creating bird eggs with unfeasibly thin eggshells
What is biomagnification?
The process of concentrating contaminants the higher up on a food chain you go
What were the upsides of banning DDT?
It helped the ecosystems recover
What were the downsides of banning DDT?
Millions of preventable deaths happened
What is a major issue in creating one safe and effective pesticide?
Pesticide resistance, caused by natural selection
How do pollutants get into humans?
Ingestion, absorption, injection, inhalation
What is the difference between a poison and a toxin?
Toxins are proteins that cause bodily harm while a poison is anything that causes bodily harm
What is an acid?
A chemical that produces an acidic substance with a PH of less than 7
What is a base?
A chemical that produces a basic substance with a PH of more than 7
What is the best way to test if something is an acid or a base?
Litmus, a plant compound, turns red in acids and blue in bases
What is the formula for pH?
-log [H+], or the negative base 10 logarithmic function for the concentration of hydrogen ions in a solution
Molality vs Molarity
Molality is moles/mass whereas molarity is moles/volume
How do negative pHs work?
When the concentration of hydrogen ions is greater than 1 molarity (#moles/volume in litres)(a very very very big number)
What does pH stand for?
Power of Hydrogen
What is acid precipitation?
The raining of acids, caused by the water absorbing the toxic gases in the atmosphere
How did international agreements reduce acid rain?
They agreed to cut emissions, which reduced the toxic gases in the atmosphere to reduce acid rain
What is liming?
Liming, or acid-base neutralization, is the process of releasing a substance to react with an acid to neutralize it into pH 7, usually done with limestone (Calcium Carbonate) and sulfuric acid to produce a salt and a water
Why is liming bad and what is the better alternative?
Lakes are constantly fed with acids from rivers and reducing emissions through a catalytic converter to encourage complete oxidation (carbon dioxide instead of carbon monoxide)
What are scrubbers?
Devices with sorbents to capture the harmful gasses, especially sulfur dioxide
What is a pollutant?
Anything that can cause harm to an organism
What is pollution?
The altercation of the environment causing harm to organisms
What is toxicity?
The ability of a substance to cause harm to an organism
What is acute and chronic toxicity?
Acute happens immediately while chronic happens through prolonged exposure
What is an LD50?
The dose that can kill 50% of a population when it is applied
Why do governments take so long to approve a drug?
They must undergo thorough testing, or else it might end up like thalidomide, which caused missing limbs when taken by pregnant mothers although it had no effect on lab rats with thousands of times the dose
What is the evaluation of risk?
The decision to accept the risks that come with any chemical
What is the difference between persistent and non-persistent pollutants?
Persistent pollutants do not break down easily while non-persistent ones do
What are bioindicator species?
Species that indicate the success of the ecosystem
What are the best bioindicator species?
Macroinvertebrates, organisms without a backbone visible to the naked eye
What are point sources and non-point sources?
Point sources are a source of pollutant that enters the environment from specific points and non-point sources offer a large dispersion of pollutants
How do excess phosphates and nitrates harm the water?
It creates algae which when they die off soak up a lot of oxygen for the decomposition process
What is NIMBY?
Not in my backyard, or the sense that people don’t know how close waste is
What happened to the ozone layer above the Antarctic?
Chlorofluorocarbons were being emitted, and when UV rays turned them into chloride ions which acted as a catalyst for the breakdown of ozone into oxygen
Why is pollution affecting aquifers?
The groundwater supply that is usually bacteria-free ends up contaminated by other chemicals
What does biodegradable mean?
Substances that can be broken down by organisms
What are hazardous wastes?
Any waste material that is either poisonous, toxic, corrosive, flammable or explosive
What percent of solvents are hazardous?
ALL
What are the 3 Rs?
In order of effectiveness, reduce, reuse and recycle
Why is recycling beneficial?
It saves a very large amount of energy needed to manufacture a new product, and prevents landfill buildup
What is a sanitary landfill?
A landfill covered each day by a new layer of earth to prevent scavengers and blowing debris and usually incorporates some sort of clay or plastic liner to prevent liquids from contaminating the earth
What is leachate?
The liquid that drains from landfills, whether it be rainwater or decomposition liquid
What are secure landfills?
Sanitary landfills but extra, including gravel, drainage pipes, etc. to store more harmful wastes
What are water hyacinths?
A plant that help in the wastewater treatment process that filters out pollutants
What do mustard and fescue grass do?
More plants that can help filter out harmful substances and reduce it into less potent forms
What is biomediation?
The process of using organisms to solve problems
What are bioreactors?
Tanks that house biomediating bacteria
What is a substrate?
The surface or material on which an organism grows
What are POPs?
Persistent organic pollutants are pollutants that break down very slowly
What are non-persistent pollutants?
Pollutants easily biodegradable into non-polluting substances
What is a dilution?
A reduction of concentration
How much is a mole?
The number of particles in 12 grams of Carbon 12, or 6.02214076 × 10^23 particles, known as Avogadro’s constant. the #grams/mole is also equal to the atomic mass of an element/compound
