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Environmental Chemistry

Hydrogen cyanide

In less than a 125 words, with Hydrogen Cyanide -How can we most likely be exposed to it -How we can minimize our dose -the most likely route of entry into the body and target organ -A brief description of its toxic effect hide problem

Ozone Depletion Potential (ODP)

Please see attachment for the problem. Estimate the ODP (i.e.) Ozone Depletion potential for the following CFC alternatives relative to HCFC-22. and fill in the table with the ODP values. Justify the reasons for your ranking. Compound kOH × 1012 cm3 molecule-1 s-1 ODP CHF2Cl (HCFC-22) 1.2 exp (-1650/T) 0.05 CF3CH2F (HFC-13

Benzene and Phenol: Discussion of LD50 and LDLO

With Benzene and Phenol: Does one molecules consistently have a greater LD-50 for all species? explain Are the relative LDLO for benzene and phenol as you would expect? How were the LDLO for humans obtained? How reliable are the LDLO? Explain which data you would use to determine a lethal dose for you and calculate the

Box Model for Steady-State Pollution Concentration Calculations

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

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.

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.

Catalytic converter

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?

Oxygenates

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?

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.

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

Can you please help? There are some questions that I don't get and others that I am unsure I took the right path. Please see the attachment.