Possible FRQs: Unit 7 test (chapters 14 and 22)
Directions: You will be asked to answer two of the three questions listed below (my choice), which are weighted equally; the suggested time is about 15 minutes for answering each question. Where calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is required, support your answers with relevant information and/or specific examples.
- An experiment is performed to test the toxicity of methlmercury using brine shrimp as a test organism. Six different concentrations of methylmercury solutions are prepared in separate petri dishes, and 100 brine shrimp are placed in each dish. After 48 hours, the number of brine shrimp that have died is counted and recorded. The results of this experiment are shown in the table below.
Methylmercury Concentration (%) / Number of Dead Brine Shrimp
0.0001 / 10
0.001 / 10
0.01 / 20
0.1 / 55
1 / 90
10 / 100
(a)Plot these data on the blank semi-log graph provided below. Draw a smooth curve through the data points to illustrate the overall trend of the data.
(b)What is the LD50 concentration of methylmercury for brine shrimp based on these results?
(c)Mercury is a toxic pollutant.
(i)Identify and describe one specific source for mercury pollution.
(ii)Describe how mercury enters the human body and one specific effect it can have on human health.
(iii)Describe TWO specific steps, other than an outright ban, that a city or nation can take to reduce the threat posed by mercury.
(d)Explain why there are greater health risks associated with eating large predatory fish, such as tuna and sea bass, than from eating small nonpredatory fish.
- Polybrominateddiphenyl ethers (PBDEs) are ubiquitous chemicals with many industrial uses.
(a)Identify and describe one use of PBDEs.
(b)Studies have shown that PBDEs act as endocrine disruptors.
(i)Describe what an endocrine disruptor is.
(ii)Describe how PBDE exposure affects human health.
(c)According to the Washington State Department of Health, the EC50 of PBDEs in rainbow trout was 10 mg/kg bodyweight following 120 days exposure.
(i)Use the EC50 from rainbow trout to calculate the EC50 for a 70-kilogram person. List your answer in grams/person.
(ii)Assuming that a population of trout contains 1 mg PBDE per kg bodyweight, calculate the mass of rainbow trout, in grams, that a 70-kilogram person would have to eat to reach their EC50.
(d)Explain why breastfed babies are at a greater risk of PBDE exposure compared to formula-fed babies.
(e)PBDEs and other chemicals are subject to federal control
(i)Identify one U.S. federal agency that monitors and regulates PBDE usage.
(ii)Describe one U.S. federal law that gives regulatory authority to the agency listed in your answer 2(e)(i).
- Wellington and Apollonia are expecting a baby and are trying to decide whether to use cloth diapers or disposable diapers. A complete set of cloth diapers (newborn to potty training) costs $300. Disposable diapers cost an average of $0.20 each. A typical baby will need their diaper changed 8 times per day.
(a)Calculate the amount of money, in dollars, that the expectant couple would spend on disposable diapers in one year.
(b)Calculate the difference, in dollars, between using cloth diapers and disposable diapers for three years (a reasonable age of potty training).
(c)According to the CDC, 4.0 x 106 babies are born in the U.S. each year. Calculate the total number of diapers thrown away in one year if all of the babies wore disposable diapers.
(d)Wellington and Apollonia are concerned about more than just their wallets.
(i)List and describe TWO negative impacts that disposable diapers have on the environment.
(ii)List and describe ONE negative impact that cloth diapers have on the environment.
(e)Describe TWO viable strategies that a local government might use to decrease the number of disposable diapers used.
- Read the following news article from the Tacoma News Tribune and answer the questions that follow.
Agreement reached in garbage strike
DOUG ESSER, August 2nd, 2012
SEATTLE — Awaste collection company and its striking drivers announced a tentative agreement Wednesday in an eight-day walkout that has left bags spilling from trash cans in Seattle and nearby cities. The company had announced Tuesday that it had decided to begin hiring permanent replacements.
Waste Management Inc. and Teamsters Local 117 said the agreement on a six-year contract came after a confidential meeting between the parties’ lead negotiators. Teamsters leadership will recommend that striking recycling and yard waste truck drivers approve the pact in a vote scheduled this morning, the two sides said in a statement. Terms of the tentative deal were not released.
Garbage truck drivers, represented by a different Teamsters local, have been honoring the strikers’ picket lines. Due to the timing of the ratification vote, recycling and yard waste collection will be limited Thursday, the statement said.
The walkout that began July 25 has affected 217,000 customers in King and Snohomish counties. Some business owners have angrily paid to dump their own trash. In neighborhoods, flies were circling curbside garbage bins where trash has started to stink in the summer weather. The Washington Fish and Wildlife Department urged residents to keep garbage enclosed to avoid attracting raccoons and bears.
“We are pleased to have negotiated a contract that recognizes the professionalism of our members,” said Tracey Thompson, secretary-treasurer of Local 117, which represents the 150 recycling and yard waste drivers. “We are extremely pleased that we reached an agreement on a new contract that delivers a solid compensation package to our hardworking and professional drivers,” Waste Management spokeswoman Robin Freedman said in the statement. She asked for customers’ patience as the company works to “fully recover from this unfortunate situation.”
Waste Management said its most recent previous offer was a six-year deal that would raise average salaries from $58,000 to $68,000 a year. If benefits are included, that offer was worth $98,000 a year to a driver at the end of the sixth year, the company said.
(a)Pierce county citizens produce an estimated 3.5 pounds of garbage per person per day. Using this rate, calculate the amount of garbage, in pounds, that the 217,000 King and Snohomish county customers produced during the 8-day strike.
(b)Identify TWO potential fates of municipal waste following curbside pickup. Explain ONE advantage and ONE disadvantage for each waste disposal method.
(c)Describe ONE viable strategy for reducing the amount of waste generated in the U.S. Be specific.
(d)Waste that is toxic, reactive or corrosive is considered “hazardous waste.”
(i)Describe ONE legal method of hazardous waste disposal.
(ii)The amount of electronic “E-waste” generation is growing rapidly. Explain why e-waste is classified as hazardous waste.
(iii)Identify and describe ONE U.S. federal law related to hazardous waste.