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Environmental Chemistry

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

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

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.

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

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.

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

Stoke's Law problem (3 parts)

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

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

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?

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

ARCHAEOLOGICAL CHEMISTRY

Answer the following questions, showing calculations and equations where appropriate: 1. Your analytical technique directly and accurately measures the concentration of iron-54 in your samples. How would you calculate the total iron concentration from these concentrations? What if you wanted to know the iron-oxide concentrati