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    Environmental Chemistry

    Box Model for Steady-State Pollution Concentration

    A Power plant is the main point source of SO2 emissions for a 25 km2 area. Estimate the steady-state concentration of SO2 for this area from this point source given the following temperature data. Windspeed= 5km/hr. The concentration of SO2 is 111.1 g/s. Height (in meters) Temperature (K) 0 300 500

    Graphing SO2 Concentrations around a Power Plant

    1) A power plant burns 10^4 kg hr-1 of coal containing 2.5% sulfur. The effluent is released from a single stack of height 70 m. The plume rise is normally about 30 m. The wind on the day of interest, which is a sunny summer day, is blowing at 4 m s-1. There is no inversion layer. a) Plot the ground-level SO2 (sulfur dioxid

    Unit Conversion Dimensional Analysis

    Typical rate of deposit of dust (dustfall) from unpolluted air was reported as 10 tons per square mile per month. Express this dustfall in milligrams per square meter per hour.

    Calculate how much energy a wind turbine produces in a year.

    Assume a wind turbine with a hub 50 meters above the ground, a rotor diameter of 40 meters and a wind-conversion efficiency of 25 percent. The turbine operates in an area with an average wind-power density of 550 watts/sq meter at 50 meters altitude. How much electricity (kwH) can the turbine generate per year? Wind densities

    Concentration of Iron in a Waste Stream

    The determination of iron in industrial waste stream is often carried out by reacting the water sample with o-phenanthroline to form a red-orange complex that absorbs at 510 nm. Using the data shown in the following table construct the standard calibration curve and determine the concentration of Fe in the waste stream. The cuve

    Grams of Lithium Carbonate Formed

    (a) Aqueous lithium hydroxide solution is used to purify air in spacecrafts and submarines because it absorbs carbon dioxide according to the equation: 2LiOH(aq) + CO2(g) -> Li2CO3(aq) + H2O(l) The pressure of CO2 in a cabin with a volume of 2.4 x 105 L is 7.9 x 10-3 atm at 312 K. A solution of LiOH of negligible volume is

    Bubbles and Bicarbonate

    (a) A small bubble rises from the bottom of a lake, where the temperature and pressure are 8ºC and 6.4 atm, to the water's surface, where the temperature is 25ºC and pressure is 1.0 atm. Calculate the final volume (in ml) of the bubble if its initial volume was 2.1 ml. (b)The percent by mass of bicarbonate (HCO3-) in a

    Will Banning Phosphate Builders Slow Eutrophication?

    Assume that algae need carbon, nitrogen and phosphorus in the atomic ratio 106:16:1. What is the limiting nutrient in the lake that contains the following concentrations: total carbon = 20 mg/L, total N = 0.80 mg/L and total P = 0.16 mg/L? If it is known that half the phosphorus in the lake originates from the use of phosphate d

    Renewable energy sources are essentially inexhaustible.

    See attached file for full problem description. 13. Which response includes all of the following substances that have H = 0, and no other substances? I. HCl(g) II. Na(s) III. HCl(aq) IV. F2(g) A.I and II B. II and IV C.I, II, and IV D.II E.I, II, III, and IV 14. Renewable energy sources are esse

    An area-source box model for air pollution above a peninsula of land

    37) Consider an area-source box model for air pollution above a peninsula of land. the length of the box is 15 km, its width is 80 km, and a radiation inversion restricts mixing to 15 m. Wind is blowing clean air into the long dimention of the box at 0.5 m/s. Between 4 and 6 pm there are 250,000 vehicles on the road, each being

    Estimate of NOx concentration given emission volume and wind speed.

    36) A freeway has 10,000 vehicles per hour passing a house 200 m away. Each car emits an average of 1.5 g/mi of NOx, and winds are blowing at 2 m/s across the freeway towards the house. Estimate the NOx concentration at the house on a clear summer day near noon (assuming that NOx is chemical stable).

    Tetrachloroethylene Biochemical Oxygen Demand problem

    Info: BOD: Biochemical Oxygen Demand BOD5 is the total amount of oxygen consumed by microorganisms during the first five days of biodegradation BOD5 = (DOi - Dof)/(P) this is the five-day BOD of a diluted sample Where DOi = the initial dissolved oxygen (DO) of the diluted wastewater DOf = the final DO of

    Waste water mass balance problem

    Info: BOD: Biochemical Oxygen Demand BOD5 is the total amount of oxygen consumed by microorganisms during the first five days of biodegradation BOD5 = (DOi - Dof)/(P) this is the five-day BOD of a diluted sample Where DOi = the initial dissolved oxygen (DO) of the diluted wastewater DOf = the final DO of

    Changes in Carbon

    The total mass of Carbon contained in fossil-fuels that were burned in the world from the year 1750 to the year 2000 was estimated to be 2.7 x E14 kg C. The amound of carbon released as CO2 from agricultural expansion and deforestation over this period is estimated to be 1.3 x E14 kg C. The concentration of CO2 in the atmosphere

    Photosynthesis related question

    A) Photosynthesis is estimated to produce 340.0 g (dry weight) of plant matter per square meter, 50% of which is carbon. Calculate the total number of grams of carbon "fixed" each year by 1000 square meters. b) The photosynthetic reaction can be represented as: 6CO2 + 6H2O -> C6H12O6 + 6O2 Of the glucose produced, 40.0% is

    Solar panels and heating water

    Should you install a solar water heater? The average home has a 200 liter hot-water tank, which is effectively drained and replenished three times per day. Assume that the entering tap water is 19 degrees Centigrade and is heated to 53 degrees Centigrade. Given an average energy from sunlight of 1.53 kJ/cm2 per day, how large wo

    Radioactive dating using carbon 14 concentration

    The well-preserved remains of a now extinct woolly mammoth is entombed in the permafrost lands of Siberia. Scientists have conducted carbon dating experiments on plant debris found in the stomachs of this mammoth. The C-14 activity of the mammoths was measured at 1.499999999999999 disintegration per minute per gram of carbon.

    Converting Corn into Ethanol

    (a) An acre of corn can produce about 375 gallons of ethanol, using only the kernel of the corn for conversion to ethanol. Assume the energy input to produce an acre of corn is 15000000 kJ. If a gallon of ethanol has an embodied energy in the ethanol of about 80000 kJ, calculate the ratio of embodied energy in the ethanol to th

    How much energy is required for wattage.

    If a customer replaces a 85 watt bulb with an 20 watt compact fluorescent bulb that lasts 5000 hours, how much less coal (lbs)will be used to generate the electricity that is saved? Assume the electricity is generated with 30% efficiency and the energy content of the coal is 30 kJ/g.

    Catalytic Converter in Automobiles

    The catalytic converter on your automobile contains small amounts of a precious metal catalyst. Which of the following components would you expect to be decreased in your tailpipe emissions by a properly functioning catalytic converter in your automobile (Choose all that apply): - water - carbon monoxide - carbon dioxide -

    Increased auto compression ratios

    The compression ratio of today's cars is so much higher than in cars of years past. a) What is the major advantage of increasing the compression ratio? b) How must the gasoline change in order to burn smoothly and evenly in engines with higher compression ratios?

    On the Greenhouse Effect and Global Warming

    Many scientists suggest that there is a relationship between the greenhouse effect and global warming. Even if you do not believe in either concept, describe the relationship that these scientists are claiming between greenhouse effect and global warming.

    Oxygenates - Clean Air Act

    The Clean Air Act mandates that certain metropolitan areas must add oxygenates to the gasoline that is sold in that area. What is the reason that oxygenates are added to gasoline?

    Greenhouse Effect - Reasons

    A) Even if you do not believe in the concept, describe the greenhouse effect b) Name three gases that might be responsible for the greenhouse effect