Avogadro’s Number and the Mole (Section)
A sample of the male sex hormone testosterone, C19H28O2, contains 3.88 * 1021 hydrogen atoms.: (a) How many atoms of carbon does it contain? (b) How many molecules of testosterone does it contain? (c) How many moles of testosterone does it contain? (d) What is the mass of this sample in grams?
GEOL 1010 Dr. Coulson TEST 4 STUDY GUIDE Highlight= Important Principle Highligh= Key Term Lecture 13: Hydrology Why do we care Need water to survive Finite amount of water on earth Hydrologic Cycle Ocean = biggest reservoir of water rivers/lakes have relatively small amounts of water Glaciers = second largest reservoir Groundwater = third largest Groundwater Precipitation can either hit ground and stay on surface and runoff, or go into ground Infiltrat process of water soaking into ground (groundwater) Porosit total amount of open spaces (cracks, pores) in area (%) 3 types: 1. Intergranular Pores little spaces in between grains a. Typically very small, but in large amount b. Most groundwater stored here 2. Fractures any kind of crack or opening a. Larger than Intergranular, and can store lots of water i. Do not always hold lots of water (small cracks don’t hold a lot) 3. Vugs large openings/holes a. Largest of the 3 (can be the size of caverns) b. Not very common c. Formed by some dissolving/erosion Controls of porosity determined by sediment/rock properties Sorting (shapes and sizes of sediment; how well do they fit together) (wellsorted > high porosity) If poorly sorted, the openings b/w sediment is filled with very small sediment instead of water Cementation: how well cemented sediment is Permeability how much water can move/flow in area Want high permeability > easier to extract Water table (WT) boundary of zone of aeration/saturation (everything become saturated) Zone of aeration aka unsaturated zone vadose zone everything is not saturated Zone of saturation phreatic zone everything is not saturated Groundwater supply Aquifer any layer of sediment/rock that produces water Recovered by people via wells Types: Unconfined no other material that messes up flow Selfsustaining Aquitard prohibits water Confined extra layer than unconfined Results in more difficulty to refill aquifer Artesian well takes advantage of high water pressure of confined aquifers Saves time and money Ideal solution: want a sloped aquifer and place well at bottom of slope Perched aka perch WT relatively small Drilling shallow well = cheap and easier Recharge how fast are you filling aquifier Discharge how fast are you losing water If recharge > discharge, water table rises Can cause issues Construction in water isn’t easy… If recharge < discharge → overdrafting Cone of depression water table around well is sucked down Subsidence ground concave in a little removing water quickly can alter structure of ground example California 1970s high elevation than now Salinity contamination close to Coast could result in salt water going into well water Desalination getting salt out of water adds a lot of expense to Water bill GW Movement Typically very slow (a few inches a day) Good: most water stays in same place for long time Bad: if water gets contaminated, then it sits there for a long time Erosion can occur (slowly) GW contains dissolved substances CO 2and SO Dissolve carbonate rocks Causes caves, sinkholes, etc. Case Study: GW Contamination Love Canal, Niagara Falls NY Early 1900s they tried to build a canal but never finished 1940s: disposal of chemical waste in these unfinished canals Buried it and left it 1950s/1960s: large population increase in area Chemical company sells land for $1 1960s/1970s: lots of rainfall and construction Chemical contaminants rising Increased health issues 50% of babies born with defects 1978 homeowners learn there are 21,000 tons of waste underground Kids would fall on ground and have a burn mark August 7, 1978 President Carter declared state of emergency 1980s Superfund Act clean up areas with national help because one state couldn’t handle it Chemical components responsible and had to pay millions 2008 survey of 4 states found 500,000 kids in schools 3.5 billion) people live within 120 miles of coastline Coasts still on continental crust Several forces act on environments (complicated process) Changing just one factor can cause a huge impact Processes: Tides Tidal Flats area of land going above/below water during high/low tide High tide/low tide controlled by moon High tide: sides facing toward and away from moon Low tide: sides ‘in between’ Tide height: Hawaii has tidal range of 12 ft Bay of Fundy has range of 40 ft Affected by amount of land around it Waves: Wavelength distance between waves Changes as they approach shore The slow down Bottom of wave drags on seafloor Wavelength decreases Wave height gets taller Wave refraction waves curve slightly Waves come in at angle and therefore slow down at different speeds (leads to a curved pattern) Longshore current zigzag pattern that forms by waves pushing into shore and back out Longshore drift process of longshore current picking up and depositing sediment Shoreline Features Depend on tectonics, rock type, sea level fluctuations, storm size/strength, etc Types of coastlines: Emergent shoreline is uplifted/exposed stacks steep, small islands (typically no beach) Terraces large, flat, starlike areas Each ‘step’ represents a former beach Submergent coastline sinking or water level rising (opposite of emergent) Long, wide beaches and coastal plains Spit long, large deposits of sand still connected to land but extend out into water Barrier islands same as spit but NOT connected to main land Unstable (due to lots of forces acting on it, even though it is just sediment deposit) Constantly in motion Offshore Features Continental margin edge of continent under water that marks transition from continental to oceanic crust Types: Active location of plate boundary Passive no plate boundary (ex: east coast USA) Parts: Continental shelf close to shore and flat Good for fishing Lots of nutrients Results in lots of predators (fish) Economically important (fossil fuel hotspot) Continental slope edge of shelf that slopes downwards Continental rise right before oceanic crust Abyssal plain official start of oceanic plate Coastal Erosion Can occur on emergent/submergent coasts Natural process Hazardous due to proximity of people to build on shores Case Study: Cape Hatteras Lighthouse Outer Banks, NC Strong longshore currents 1868: 1500ft inland 1998: 120ft inland Average rate of erosion: 10.6ft/yr To fix this, 19992000: lighthouse moved 2900ft inland over 23 days Cost: $15 million Dealing with Coastal Erosion: 1. Zoning build farther inland Setback distance how far inland is safe calculated/expressed with Erosion Lines (E lines) line along coast marking where erosion will move shoreline in future Ex: E10 line shows where shore will be in 10 yrs Formula: (erosion rate)(interval)=Eline distance How far is considered safe National: E60 or further back 60 years due to building life expectancy of 50 years SC: E40 or further back Tourism = #1 resource for SC 2010: tourism = $1.8 billion People want to be close to beach 2. Barriers Weaken waves Keep sand from moving away Less erosion, more stability Seawalls parallel to coastline Drawbacks Block wave so it does not erode coast as much Relatively effective Expensive Wear down in short time Need repairs Not visually appealing Tourism affected Groins perpendicular to coast Shut down longshore drift (NOT stopping waves) Builds land on one side, but erodes heavily on other Private properties are affected Expensive 3. Beach (Re)nourishment replacing eroded sand/sediment Truck in or spray sand back on beaches Case Study: Miami 1950s: erosion wiped out beaches 1960s1970s: beach nourishment processes: HUGE success 1980s: cost a lot but highly effective New Jersey copies and loses sand due to erosion in short time Redo it and change some things = success Drawbacks: Wildlife issues (nothing can survive in tight, compact, imported sand Lecture 15: Nonrenewable Energy **Geology in the News : Archean Eon glaciation (3.5 Ga) may have been greater than previously thought Energy Runs everything ( technology, heating) Affects personal budgets and national economics Political topicwhere to get energy from Energy Sources Renewablesources of energy that will quickly replace itself Time scale = useful for humans Nonrenewablesources that will never replenish or will replenish too slowly for humans to take benefit from Fossil Fuels ~82% of energy in the US comes from Fossil Fuels Coal 22.6% Oil 36.8% Natural Gas 22.9% Hydroelectric 6.3% Nuclear 6% All other 1.4% How much is there Reserve amount of something you have ready for use Resource all of the stuff you have ready to use and the stuff you know about but it's not ready to use All known stuff Advantages of Fossil Fuels Historically cheap and abundant Technology well developed We know how to use Fossil Fuels INfrastructure built to run on them Gas in cars Burning coal Disadvantages of Fossil Fuels Nonrenewable Deposits not uniformly distributed Causes trouble between countries Costs going up Environmental damage Types of Fossil Fuels Hydrocarbons Hydrogen and Carbon Combustible HC compounds Requires: Area of high biological productivity Massive amounts of biomass Continental shelf = good place Organisms have short life span and constantly dying and decaying Relatively low oxygen in water/sediment Type of Hydrocarbon: Methane and Natural Gas Advantages Resources growing in recent years Burns much cleaner than other fossil fuels Price often cheaper than oil Disadvantages Safety issues Sour gas ( contains H2S) Filtering the gas is expensive and takes a lot of time Still contributes to atmospheric CO2 buildup Combustible Too much can cause large fires Oil Hard to get oil to form Right temp and pressure to form Oil window Right conditions for oil to form ( 25 km, <150 degrees celsius) World Oil Supply 62% in the middle east 22% in Saudi Arabia 2.5% in the US Long time agomiddle east was under water with right conditions so a lot of oil formed there Everybody friendly to Saudi Arabia because they have so much oil US Oil Production and Consumption US uses 7.5 billion barrels each year 2010: US imported 61% of the oil we needed Cost = $337 billion $640,000 per minute 1973 Importing 50% 2004 60% 2007 75% 2010 61% US Consumption was greater than US productionnot good Fracking Hydraulic Fracturing Boost in production in recent years Uses pressurized fluids to shatter rock below ground (creates permeability) Advantages: Get oil out of areas where traditional drilling cannot Disadvantages: Contamination Not pure water is being shot into the ground Contains chemicals Chemicals get into ground water supply May 2015 water supplies in PA contaminated with fracking fluids FIghts over regulating the industry Possible to do fracking safely Put to follow regulations causes time and effort and drives the cost up Seismic Activity Busting rock underground causes seismic activity Example: Oklahoma Had to pass rules and regulations because of seismic activity due to so much fracking How much oil is left Debatable Lots Find new deposits Improve technology to get more out of deposits Little Existing fields producing less New oil fields being found less often Case Study: ANWR Arctic National Wildlife Reserve Original resource estimated 2030 billion barrels Original reserve estimated 412 billion barrels Should you drill in ANWR Lots of oil Land protected Prodrilling Side 30 billion barrels = enough to last the US 60 years Free the US from foreign oil Lower gas prices Only a tiny area of ANWR affected 2000 acres of 19 million acres used for drilling Problems: 30 billion barrels Assumes all 30 billion barrels of the resource will be available Not realistic amount Resources vs. Reserve Free from foreign oil The US imports 5 billion barrels per year Not actually free from foreign oil Lower gas prices OPEC production drives gas prices not US supply Not all ANWR oil would be used by US Tiny area drilled The small area to drill in does not include infrastructure Roads Houses Communities Pipelines The area around it will be affected Nodrilling Side Only 12 billion barrels not enough to fuel the US for even 2 years Spills devastate the environment Risk of ruining the protected land Problems: Spills Exxonvaldez cleanup cost>$2 billion 20 years later oil was still on beaches Gulf spill cost $40 billion Not all paid by gas company, but rather paid by tax dollars 12 billion barrels is enough for 2 years Assumes that there are 12 billion barrels available Production rate: 12 bbls in 2 yrs = 6 bbls/yr Impossible to pump that quickly Other Oil Sources Oil Shales and Tar Sands shales and sands with high organic content Problem: oil not fully formed yet Can mine rock and cook it to complete process to get oil Advantages: Extensive deposit Estimated shale resource has 4x more oil than Saudi Arabia Estimated Sands is 2x global oil resources Disadvantages: Produce more greenhouse gases than other fossil fuels 2550% more Carbon Dioxide produced than normal oil Not profitable at low oil prices Cooking uses energy to make energy Extensive mining operations 13 million tons of shale to fuel US for one day Uses lots of water 72 billion gallons of water to produce enough shale oil to power the US for 1 day Coal Lots of biomass Low oxygen Forms in swamps and bogs Stagnant water Not a lot of exygen Formation: Peat (50% Carbon) Lignite (70% Carbon) Bituminous coal (7090%) Anthracite coal (90+%) Advantages: US coal reserve big enough to last 100+ years Disadvantages: More pollution than other fossil fuels 25% more Carbon dioxide than oil Mercury, arsenic, etc produced in burning and mining Ash disposal 130 tons/year in US Coal burning releases sulfur Causes acid rain Effects: Weathering damage Causes problems in environment Leaches nutrients out of soils **Geology in the News : New evidence supporting Anthropocene hypothesis Strata forming today contains evidence of human activity Nuclear Energy Nonrenewable Fission splitting an atom into smaller parts Large amount of release of energy (radiation) Must safely harness energy Uranium ore = key element Ore rock/sediment with high concentration Yellowcake processed uranium ore Extracting uranium from ore 235U and 238U separated Very complex: must use centrifuge Want to filter out some of 238U; not complete Power plant: 35% enrichment Weapons: 90% enrichment 235U is what we want more of Firing neutrons takes time and energy Splitting 235U atoms starts chain reaction Problem: easy to get out of control cooling system removes heat energy Requires water (4 million gallons/yr in some plants) Advantages: Large US reserve ~30 yr supply Reduce carbon emission Decrease fossil fuel dependence Produce very large amount of energy 1kg Uranium = 3 million times amount of energy than 1kg coal Good safety record Current US use: ~100 plants use amount 20% US electricity Use declining since 1996 Half of active plants will close by 2020 No new reactors or plants built between 19782010 48% of ones ordered before 1878 never built Nuclear Disadvantages: Nuclear electric price tripled between 19701990 Reactor safety (people fearful) Nuclear proliferation Are they making weapons or electricity Waste disposal Radioactive waste Average power plant crates 2530 tons/yr 2007: US had 50,000 tons stored radioactive waste Radiation varies which means safety varies Types: LowLevel (LL) not too much radiation; pretty safe Things were not initially radioactive Class AC: A=less radioactive than B, which is less than C GTCC greater than class C Intermediate level in Europe HighLevel (HL) main types from power plants/weapons research Requires heavy shielding and deep burial Globally generate ~ 12,000 tons/yr Types: Spent nuclear fuel 20 tons/yr/plant Transuranic beyond uranium on periodic table Long halflife (>20yrs) Generated during weapons research Longterm problems What to do with waste Store it ensure stability and safety Only 3 LL waste sites in US Clive, Utah Only accepts A Richland, Washington Accepts AC from 11 NW states Barnwell, SC Class AC from other 39 states 2008: closed to all but 3 states HL waste sites Yucca Mountain = US 1st site for spent fuel Supposed to open in 1985: hasn’t started Geologic concerns (earthquakes, faults, etc) Legal challenges: ‘not in my backyard effect’ Wanting benefits of nuclear power but don’t want it that close Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM Only US site for transuranic 20 yrs planning ~½ mile underground carved into 3000 ft thick salt Containers must not be high temp, cannot contain fluid, and must be ventilated to prevent explosion Longterm plans: Site expected to be full by 2070 Monitored for safety until 2170 Then marked as offlimits for drilling, excavation, etc until 12,170 Other storage ideas: Dump in ocean Put in subduction zones Launch into space NONE of there are good ideas Use it Transmutation using as a resource Big in 1970s until banned in US Currently being revisited in Europe 137 Cs used for food irradiation 241 Am used for smoke detectors Radiation Levels Lots of units (curies, becquerels, grays, rads, etc) Rem dose (amount) x quality factor (how likely it will cause biological problems) Annual exposure from natural sources in millirems (mrem): Cosmic rays 30 Radon 95 Medical 100 Fallout 4 Terrestrial 55 Total 284 (0.3 rem) How much is safe/unsafe <5 rem/yr = no problem 520 rem = problem longterm (higher risk for cancer, etc) 20100 rem = mild radiation sickness 200+ rem = hair loss, ⅓ chance of death 600+ rem = 100% fatality rate within 14 days Contamination 108+ sites in US considered unsafe Accidents, mismanagement, storage, etc Ex: Oak Ridge National Lab, TN Over 167 sites where contaminants were released Reactor Failure: Three Mile Island PA 1979: partial core meltdown No serious radiation released (still scared everyone) Caused 30 year gap of no radiationrelated activity Chernobyl 1986 Fallout 30x> than bombs on Japan 336,000 people permanently evacuate 19 mile exclusion zone exists today Lecture 16: Renewable Energy **Geology in the News: estimated 75% of species going extinct leave no record Implies that modern species could go extinct without scientists knowing Renewable Energy Basics General Points Each type has advantages/disadvantages No one source will provide all energy; need varied approach Advantages Abundant Produce little pollution Low maintenance Safe Disadvantages Technology still being developed Expensiveusually ‘bottom line’ for people Infrastructure compatibility Acceptance by society Solar All sunlight for 1 hour = 1 year's supply of energy How can we harness Solar Farms use mirrors to reflect sunlight onto receiver Solar Electricity capturing sunlight and turning it directly into electricity ( Photovoltaics(PV)) PV cells (PVCs) materials used to complete photovoltaics Always improving Currently at 45% efficient New organic materials being studied Using ~7.5% of Sahara desert land for solar farms = provide ½ of world's energy needs Assumes 1015% efficiency Energy payback amount of time to generate enough energy to offset amount used to start Since 2000 solars EPB dropped 23 years Disadvantages Insolation Variation rain/clouds would hinder as would night Some pollution from make older PV cells Where to put solar farms SW US People want to build on national parks, wildlife area, etc Reduces cost but could affect endangered species Hydroelectric Using water for energy turns turbines to make electricity Advantages Does Not pollute water Quick profit 5 years to recover plant construction cost Disadvantages Reservoir creation floods areas Dams alter downstream environments Site selection want a big river with lots of flowing water Good spots already taken Efficiency Safety Case Study: Banqiao Dam Built to resist 1000 years flood 1975 Aug 672000 years flood 41+ included rain in one day Wave 6 mile wide 20 ft 171000 died Tides and Waves Convert kinetic energy into electricity Old devices too complicated New buoy system is 2 components Advantages Simple device Consistent Concerns: Rough environment erosion, hurricanes, storms, wildlife Changes to coastal environments Reduces wave energy Some areas far from coasts Effects on wildlife Wind Power Winds generate 5x more power than total global energy consumption Advantages: Cost down almost 80% over 20 years Energy payback ~ 1 year Disadvantages Not consistent in many areas Areas defined by classes (17)