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# Environmental Chemistry

Radioactive radon gas (222Rn) enters an average building at a rate of 5 picocuries per second per square meter of foundation area. Consider a house with a foundation of 400 square meters and a volume of 1000 cubic meters. Assume the house if well designed for energy conservation so that the ventilation rate is low and only one t

### Electricity: Power Generation by Wind Turbine.

Assume a wind turbine with a hub 50 meters above the ground, a rotor diameter of 65 meters and a wind-conversion efficiency of 25 percent. The turbine operates in an area with an average wind-power density of 300 watts/sq meter at 50 meters altitude. How much electricity (kwH) can the turbine generate per year?Wind densities gre

### How much electricity can a turbine generate in one year?

Assume a wind turbine with a hub 50 meters above the ground, a rotor diameter of 50 meters and a wind-conversion efficiency of 25 percent. The turbine operates in an area with an average wind-power density of 500 watts/sq meter at 50 meters altitude. How much electricity (kWh) can the turbine generate per year? Wind densities g

### Concentration of Fe2+ in equilibrium with Fe(OH)3 Using Nernst

At pH 6.00 and pE 2.60, what is the concentration of Fe2+ (mol/L) in equilibrium with Fe(OH)3? Use the Nernst equation and the Ksp for the solubility of solid iron (III) hydroxide.

### Comparison of Chemicals/Compound Properties

I need some help in questions pertaining to the comparison of chemicals and compound properties: 1. Explain in terms of viscosity and intermolecular bonding why (10-30) weight motor oil protects your car's engine better in the winter time and (20-40) better in the summer time. 2. Explain why in terms of surface tension, why

### What percentage of solar energy is converted to chemical energy in photosynthesis?

a) Photosynthesis is estimated to produce 330.0 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, 20.0% is

### NTA Fraction

What is the fraction of NTA present after HT2- has been brought to equilibrium with solid PbCO3 at pH 7.00, in a medium in which [HCO3-] = 1.00E-3 M? Hint: Use the equilibrium constant expression to solve this problem.

### Collection area of solar water heater

The average home has a 200 liter (50-60 gallon) hot-water tank, which is effectively drained and replenished three times per day. Assume that the entering tap water is 19 degrees C and is heated to 51 degrees C. Given an average energy from sunlight of 1.53 kJ/cm2 per day, how large would the collection area (in m2) of a solar w

### What Mass of Carbon is Needed to Increase Average CO2 by 170 ppm

Taking the mass of the atmosphere to be 4.3E15 metric tons, what mass of carbon must be burned in order to increase the average carbon dioxide level in the atmosphere by 170ppm by volume (in metric tons)?

### How many grams of gasoline are needed to raise the CO?

Assume that an incorrectly adjusted lawn mower is operated in a garage such that the combustion reaction in the engine is: C8H18 + (17/2)O2 -> 8CO + 9H2O If the dimensions of the garage are 3.0 by 5.0 by 5.0 meters, how many grams of gasoline must be burned to raise the level of CO in the air to 1000 ppm by volume at STP?

### Imported Petroleum

Petroleum consumption in the US in 1990 supplied about 34.6E15 kJ of energy. Of this quantity, about 14.3E15 kJ was supplied by foreign sources. The transportation sector is the major user of petroleum, accounting for 23.2E15 kJ of consumption. Overall automobile fuel economy in the US was about 21 miles per gallon in 1990. Aut

### Effects of higher MPG in US petroleum consumption

Petroleum consumption in the US in 1990 supplied about 33.7E15 kJ of energy. Of this quantity, about 15.9E15 kJ was supplied by foreign sources. The transportation sector is the major user of petroleum, accounting for 23.2E15 kJ of consumption. Overall automobile fuel economy in the US was about 21 miles per gallon in 1990.

### Finding Eh of Uranium Isotopes

I need to find the Eh (electromotive force) of this solution before I can procede: The solution has U4+ / U3+ = 100 Please see the attachment.

### Carbon Dating and Isotopic Fractionation

I was given lab data on a sample of organic chemistry, and I need help dating it. The data is as follows: 1. the delta value for the 13-C (carbon 13) = -7.2 2. 14-C (carbon 14) activity = 8.16 dpm/g I need help calculating the age of this carbon, and if possible, corrected for isotopic fractionation.

### Natural Products - Limonene

I am having a little trouble with finishing this problem Question: Limonene, C10H16, a terpene product found in orange, lemon, and grapefruit peel, absorbs only two molecules of hydrogen, forming p-methane, C10H20. Oxidation by permanganate converts limonene into VIII. a) How many rings if any are in the limonene Well fr

### Water processing problem

Write the reaction between ferric chloride and lime slurry that results in precipitation of Fe(OH)3. For a dosage of 40 mg/l FeCl3: What is the required stoichiometric addition of lime expressed as CaO? How many pounds of Fe(OH)3 are produced per million gallons of water treated?

### Petroleum consumption in kJ

Petroleum consumption in the US in 1990 supplied about 35.6E15 kJ of energy. Of this quantity, about 14.4E15 kJ was supplied by foreign sources. The transportation sector is the major user of petroleum, accounting for 23.2E15 kJ of consumption. Overall automobile fuel economy in the US was about 21 miles per gallon in 1990.

### Stoke's Law problem (3 parts)

Stokes' Law describing partial sedimentation is given by: Rate = [(gd^2)(&#916;&#961;)]/18&#951; where g = 9.81 m s^-2 is gravitational acceleration. &#916;&#961; is the density difference between particles and the air, air viscosity of &#951; = 1.67E-4 g cm^-1 s^-1 and d is the particle diameter in centimeters. a. Calcula

### Conversions of oxygen radicals from ppmv

During a photochemical smog episode in a coastal city, the steady-state concentration of oxygen radicals at ground level was measured to be 0.09 ppmv at 25 degrees celsius. Convert this value to: a. partial pressure in atm b. the molarity scale c. the molecules per cm-3 scale

### Fraction of NTA after equilibrium is reached

What is the fraction of NTA present after HT2- has been brought to equilibrium with solid PbCO3 at pH 7.00, in a medium in which [HCO3-] = 1.75E-3 M? I've been trying to solve this using the equilibrium constant equation, but I just can seem to set it up and solve it correctly. Please help! Thanks!

### Calculating increase of BOD in water

If 900 kg of n-propanol are accidentally discharged into a body of water containing 1e8 liter of water. By how much is the BOD(mg/L) (biochemical oxygen demand) of this water increased? I don't even know what to do with this problem, please help and show me how to do it step-by-step... Thanks!

### Stokes Law and Particle Sedimentation

Stokes' Law describes partial sedimentation. Use an air viscosity of 1.36E-4 g cm^-1 s^-1 and gravitational acceleration of g = 9.81 m s^-2. a. Calculate the weight of one cubic centimeter of air at 1.0 atm and 15 degrees celsius. b. Assume particles have a density of 2.40 g cm^-3 and are being released by a 100 m smokestack

### Landfill Leachate- Groundwater- Proof read

I am just trying to summarize what Landfill Leachate does to groundwater, and am hoping you can read this over to see if it makes sense and flows. Also, am I missing anything extremely important? I appreciate your expertise in reading this over.. It is extremely important to me. The parts I am most concerned with are the

### At an altitude of 45.00 km, the average atmospheric temperature is essentially 0 degrees C. What is the average number of air molecules per cubic centimeter of air at this altitude?

At an altitude of 45.00 km, the average atmospheric temperature is essentially 0 degrees C. What is the average number of air molecules per cubic centimeter of air at this altitude?

### Calculating bioconcentration in fat

For HCB, log Kow = 8.0. What would be the predicted concentration of HCB due to bioconcentration in the fat of fish that swim in waters containing 0.000010 ppm of the chemical?

### Wet Limestone-Gypsum Flue Gas Desulfurization System

Assume that the wet limestone process requires 1 metric ton of calcium carbonate to remove + 85.0 % of the sulfur from 4 metric tons of coal containing + 10.0 % S Assume that the sulfur product is calcium sulfate. Calculate the percentage of the limestone converted to calcium sulfate.

### Yields and pH

How many metric tons of 5%-S coal would be needed to yield the H2SO4 required to produce a 2.5-cm rainfall of pH 2.00, over an area of 100 square kilometres? I need to SEE this problem worked out, then I can do the rest of them! Hints given: Calculate vol rain, mol H+, mass of S, mass of coal.

### Aquatic Chemistry

Problem 1. Carbon sequestration technologies are being actively explored by researchers as methods to remove CO2 from the atmosphere, thereby diminishing the greenhouse effect. The most popular repository for CO2 is considered to be the deep ocean, where the CO2 would theoretically be isolated from the atmosphere for thousands o

### Archaeological Chemistry - Radiocarbon Age

Answer the following questions, showing calculations and equations where appropriate: 1. You have a radiocarbon sample analyzed and find out that the sample has 60% of the modern level of radiocarbon. Calculate the radiocarbon age of the sample using (a) an assumed 5730-year half-life and (b) a 5568-year half-life.

### Archaeological Chemistry

Answer the following questions, showing calculations and equations where appropriate: 1. Steponaitis, Blackman, and Neff (American Antiquity 61:555-572, 1996) use the following correction for bulk elemental concentrations measured in shell- tempered pottery: e' = (1000000*e)/(1000000-2.5Ca), where e' = corrected elemental conce