environmental science lab exam #2

Is Chemical A with a LD50 of 5 mg/kg or Chemical B with a LD 50 of 8 mg/kg more toxic?

5mg/kg

What is ambient air (atmospheric air in its natural state without air pollutants) made up of?

78% nitrogen, 21% oxygen .04% carbon dioxide and other trace elements such as argon and helium

List the four elements that must be present for an indoor air quality problem to exist

A contaminant, a pathway to a person, a driving force to move the contaminant, a person exposed to the contaminant

Define point and non-point sources of water pollution and give an example of each.

A poinsettia or refers to and I didn't fireable source we're pollutants are discharge such as a large petro chemical facility a feedlot are the affluent pipe from the waste water treatment plant and a non-point source refers to a pollutions that do not have a specific point of origin or our disperse such as runoff from crops in urban areas

What are secondary air pollutants? How do they form?

A secondary pollutant is formed by atmospheric reactions when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants

What is ozone? Chemical formula? How is it formed in the troposphere (what three things need to be present)? Name the two locations in the atmosphere Ozone is found in and whether or not it is beneficial in each location.

A trace gas three out of every 10 million molecules,o3, ozone is formed in the stratosphere by the reaction of ultraviolet radiation striking oxygen molecule this results in an oxygen molecule splitting apart and forming atomic oxygen 02 plus HV equals oh+ oh atomic oxygen can now react with molecular oxygen to form ozone 03

Define acute toxicity, chronic toxicity

Acute toxicity happens quickly and chronic toxicity develops only after repeated exposure

Define air pollutants?

Air pollution is particular matter or gases that are added to the air by natural or human activities that can do harm to organisms

What are mobile sources of air pollution?

Any air pollution admitted by motor vehicles airplanes, locomotive and other engines and equipment that can be moved from one location to another

What are stationary sources of air pollution?

Any fixed admit her of air pollutants such as fossil fuel burning plants, petroleum refineries petrochemical plants food processing plants and other heavy industrial sources

List six air pollutants and label whether they are primary or secondary pollutants:

Carbon monoxide is primary, AutoZone is secondary, sulfur dioxide is primary, sulfuric acid is secondary, Nitrogen dioxide is primary, Sulfur oxides primary

List at least 3 indoor air pollutants

Carbon monoxide, nitrogen oxide, formaldehyde

What are the six aggregate air pollutants (also called criteria pollutants or criteria contaminants) regulated by the Clean Air Act?

Carbon monoxide, nitrogen oxides, particular matter, sulfur oxides, AutoZone, lead

What is the purpose of chlorination in wastewater treatment? What is the purpose of dechlorination?

Chlorination is to kill pathogens in the water, do you coronation is to keep from killing fish and other microorganisms

Acids are substances that release ___ions; Bases are substances that release ions Neutral pH is____; Acid pH is____; Basic pH is____ How does photosynthesis by aquatic organisms affect the pH of water? How does respiration by aquatic organisms affect the pH of water?

Hydrogen, hydroxide,Seven, 1-6, 7-14, increase in VOG can cause oxygen in body of waters to plummet in pH will become more acidic

Define LC50 and LD50. How do they differ?

I'll D50 is orally or dermal he ingested an LC 50 is inhalation

What is the purpose of aeration (adding oxygen to the water) in wastewater treatment?

Micro organisms need air in order to do their job micro organisms breakdown pollutants in the water

What type of air pressure (negative or positive) would you use for a laboratory where hazardous chemicals are stored?

Negative low pressure

Describe the process of eutrophication (what causes it, what it is and what is the end result of the process).

No trades from fertilizers use on farms get washed into a lake the excess nitrates cause algae to grow fast and start to cover the lake services then the algae completely massive surface of the leg and blocks out sunlight needed for photosynthesis the bottom plants die because of that and the allergy starts to die too and then nature and his son out next bacteria starts to do you compose the dead plants and algae next the bacteria goes through cellular respiration as it decomposes the algae implants are uses up oxygen in the leg then the measure of dissolved oxygen consistently decreases because of the bacteria goes through the cellular respiration along with other animals with limited oxygen then why with all the oxygen depleted the animals eventually suffocate and die

What is PM2.5 and why is it such a concern to human health?

P.m. 2.5 are particles that are less than 2.5 µm and are potentially more damaging since they can be breathing into the lungs and may be absorbed into the bloodstream

What is the first and second largest components in municipal solid waste?

Paper and cardboard, and yard trimmings

Equations you need to know: Percent change equation [new-original/original] x 100

Percent change equation

What does the Pollution Prevention Act of 1990 state? (4 basic tenants)

Pollution should be prevented or reduced at the source whenever feasible when pollution can't be prevented waste or buy product should be reused or recycled in an environmentally safe manner if none of those things can happen the way should be subjected to a resource recovery process

What is source reduction and how does it help prevent pollution?

Reducing the amount of waste, generated, reuse, recycle

List the 4 Rs in their preferred order for pollution prevention.

Refuse, reduce, reuse, recycle, replace

What is the Air Quality Index (AQI) and how does it relate to air pollution concentrations (such as ozone and PM) in the atmosphere? What weather conditions tend to improve the AQI in a particular location?

The a QI is a color-coded index for reporting daily air quality. It tells you how clean or polluted your air is and what associated health effects might concern you. Cloud coverage, increased winds, decreased temperatures

Considering the answer to the previous question (Q15), what general statement can be made about LD50 and toxicity?

The amount of drug that produces the toxic effect and 50% of the individuals tested

What is the definition of dose?

The dose of a drug is a quantitive amount administrated or get taken by patient or intended medical effort those can be expressed as single dose daily dose or total dose

What is a threshold level?

The minimum level of stimulation required to trigger an action or observation

Define pH, acids and bases

The term PH means the power of hydrogen therefore in measuring pH we are determining the relative concentration exposed an exponential or power form of hydrogen ions. A base is a substance that releases hydrogen ions into water and acid is any substance that releases hydrogen ions into water

Define the following water quality characteristics: Electrical Conductivity Biological Oxygen Demand (BOD) Dissolved Oxygen (DO) Thermal Pollution Turbidity

Electrical conductivity is the measure of how well water can conduct an electrical current it is dependent on the amount of in organic dissolved solids such as chloride nitrate sulfate and phosphate ions with negative charge or sodium magnesium calcium iron and aluminum carry-ons it is important when evaluating water because it tells us that if the quality water is pure or not. Biochemical oxygen demand is the amount of oxygen needed by decomposers to break down such organic materials. Dissolved oxygen is dissolved oxygen affected by temperature decomposer amount sunlight amount rate of a photosynthetic activity in respiration. Turbidity is a measure of the clarity or clearness of water

Describe the steps in the wastewater treatment process (screening of solids, aeration, clarification/solids settling, filtration, disinfection). Know how wastewater is processed during the following treatment phases: a) Primary treatment b) Secondary Treatment c) Tertiary Treatment d) Disinfection

Flows through a bar screen, find screen area, oxidation ditch, clarification tank, sand filter, chlorination, dechlorination

Define xenobiotics

Foreign to nature made by man, we have made mini sliders and says that do not occur in nature many of these are of special concern to us toxicology because it is hard to predict what they will do and living systems and also because they can sometimes build up in the environment and embodies of living things because living systems did not evolve to break them down or laminate them from the body example pesticides