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Environmental Chemistry

Environmental Chemistry is the examination of biochemical phenomena that occur in natural environments. Its primary focus is on the properties of certain chemicals found in the air, soil and water. Although it studies how the uncontaminated environment works, by analyzing aspects such as natural concentrations of different chemical substances, it also takes into account the effects of human activity in each of these environments.

 

Important concepts are drawn from other Chemistry disciplines, such as chemical reactions, solubility and different analytical techniques. These concepts are then applied to specific environmental topics, such as contaminants, radiochemicals and environmental indicators, to better understand the underlying chemistry behind these phenomena.

For example, there are many chemical indicators which can be measured independently or in conjunction to assess the quality of water. The level of oxygenation, or the pH, or both of these measurements can be measured to assess whether for example, the water in a certain lake is suitable for habitation of a certain species, or whether it is in fact hazardous and sub-optimal.

Environmental Chemistry is becoming increasingly important as many Environmental Agencies use its concepts and techniques for the detection and identification of pollutants, such as heavy metal contamination from nearby industries, or urban runoff from a nearby city. Thus, although many of the concepts are drawn from different Chemistry disciplines, it focuses more on the properties of chemicals in its natural context.

Categories within Environmental Chemistry

Hazardous Materials

Postings: 28

A Hazardous Material is one that presents a risk to health or the environment.

Impeller-powered Flocculation Basin

8.7 Step-wise solution to a numerical problem related to a flocculation-based water treatment plant having a flow of 25 MGD. The plant is to employ alum coagulation, and pertinent data for the flocculation basin are as follows: detention time = 20 min, G = 35 sec^-1 (at 50 degrees Fahrenheit), GT = 10,000 to 100,000, width = 1.2

Determining groundwater hardness

Question 1: Hardness in groundwater is due to the presence of metal ions, primarily Mg2+ and Ca2+. Hardness is generally reported as ppm CaCO3 or mmol/L Ca2+. To measure the water hardness, a sample of groundwater is titrated with EDTA, a chelating agent; in the presence of the indicator eriochrome black T, symbolized as In. Er

Photorespiration

Photorespiration is considered a wasteful process that decreases the growth of C3 plants. What experiment would you propose to minimize the role of photorespiration in plants and ideally see increased growth as a result? Provide a brief description of your experiment and how you could carry out the experiment in laboratory condi

Chemistry: A gas originally occupies 20L at 24.7 psia and 5 C. What would the pressure be if the volume changed to 4.77ft3 and the temperature was 82 F? Give the answer in atmospheres.

Please show all work and steps to following: 11. In the welding shop of the XYZ Manufacturing plant you have a cylinder with a volume of 548L of a compressed gas, and the pressure gauge shows 238 psig at the room temperature 25 C. A welder was instructed to go outdoors to weld, and the temperature in Texas at this time was

Describe the nature and characteristics of PCB's.

Describe the nature and characteristics of PCB's. Why are they of importance to an EH&S or FS professional who encounters them when coming upon an incident scene where they are present? What precautions, or actions, should the EH&S or FS professional take when faced with this situation? What happens to FS personnel and their tur

Chemistry of Hazardous Compounds

Acetyl chloride is a colorless, fuming liquid used primarily in the chemical industry. a) How is acetyl chloride produced? If 915 gallons is produced and shipped, will DOT require the carrier to display the flammable placard? Explain your answer. b) When there is a bulk spill of this chemical, why is it necessary to prev

CFC's and the Ozone Layer for Chemistry Students

What is ozone and how it works as a protective molecule for our environment? What are the effects of CFCs on the ozone layer? What other alternatives you can think of to diminish environmental impact of CFCs? Draw the electron dot structure of ozone, and explain its molecular shape and properties. Is ozone a covalent

Preparation of an a,B unsaturated ketone via michael and aldol condensation

I'm wondering if you could help me answer a few questions about a lab I'm doing. We are preparing an a,b-unsaturated ketone via Michael and aldol condensation reactions. The reactants are trans-chalcone and ethyl acetoacetate (in ethanol and NaOH). This creates 6-ethoxycarbonyl-3,5-diphenyl-2-cyclohexenone. 1) A white so

Help urgent as well

Please I answered all of them except b, therefore, I need help with answer b and also could you verify my answers please for a, c, and d? if they are wrong what would it be? Thank you -The pH of uncontaminated rain water is about 5.6. The pH of rain falling in Cleveland, OH is 4.2 and that in Omaha, NE is 5.5. a. In wh

Environmental Chemistry questions

1. A) Draw the Lewis structure of chlorine nitrate. b) Write out the chemical equations showing how chlorine nitrate is formed in the stratosphere and for the reactions that convert it back to active chlorine compounds. Include reactions that occur in polar stratospheric clouds. Calculate the rate constants at

Chemistry Practice Problems

1) Free radicals (see Problem 115) are also important in many environmentally significant reactions. For example, photochemical smog, which forms as a result of the action of sunlight on air pollutants, is formed in part by the following two steps. X NO2 NO O O O2 O3 UV light Ozone damages rubber products. The product of this re

Cycling of Calcium in Nature

Please review the occurrence and cycling of calcium in nature, along with its use. Analyze and evaluate the article as to it's contemporary relevance regarding the elements availability, health implications and environmental impact.

Calculating kWh of a wind turbine

Assume a wind turbine with a hub 50 meters above the ground, a rotor diameter of 60 meters and a wind-conversion efficiency of 25 percent. The turbine operates in an area with an average wind-power density of 700 watts/sq meter at 50 meters altitude. How much electricity (kwH) can the turbine generate per year? Wind densitie

Concentration: Zinc and Toluene

1. 2g sample of harbour sediment was digested in aqua regia and then the filtered solution made up to 50mL and analysed by flame atomic absorption, giving a concentration of 4.6mg/L of Zinc. What was the concentration of Zinc, in mg/Kg in the sediment? 2. 100µL sample of petrol for analysis was diluted to 10mL with pentane c

Dealing with Hazardous Waste

7. Give your reasons for agreeing or disagreeing with each of the following proposals for dealing with hazardous waste: A. Reduce the production of hazardous waste and encourage recycling and reuse of hazardous materials by charging producers a tax or fee for each unit of waste generated. B. Ban all land disposal and incin

Global Warming, Climate Change and Albedo

1.In preparation for the 1992 UN Conference on the Human Environment in Rio de Janeiro, President George H. W. Bush's top economic adviser gave an address in Williamsburg, Virginia, to representatives of governments from a number of countries. He told his audience not to worry about global warming because, the average temperatur

OSHA Permissible Exposure Limits

Q1. Suppose that an industrial process produces the following air-contaminant concentrations for the periods shown: Period Methanol(ppm) Nitric Oxide(ppm) Sulfur Dioxide 8AM - 10 AM 50 5 0 10AM - 11 AM 150 10 1 11 AM -

Adsorption of Heavy Metals in Soil : Langmuir Equation

A peat soil was found to have the following Langmuir constants for the adsorption of heavy metals. Metal Q (adsorption capacity) k (Langmuir reaction energy) Lead (Pb2+) 36.5 1.096 Cadmium (Cd2+) 10.6 0.483 Chromium (CrO42-) 6.8 0.330 Langmuir adsorption equation qe = QkCe / (1+ kCe) Where qe is met

Use of plastics in everyday life

Discuss how plastics are used in everyday life and cutting edge technology and what the pitfalls are of plastics. The word limit is 300 words. Cite your sources.

Comparing the Amount of Coal and Uranium Required to Produce Electricity

When some large nuclear plants run at full capacity, they produce about 1900 MW of electrical power. At this rate, what mass of 235U (kg) would it consume per year if the efficiency of converting nuclear energy to electricity is 33%? How many metric tons of coal would be required to supply the same amount of electricity? Hint

Stratifiction (Layers) in a Body of Water

Draw a diagram showing the stratification in a body of water. Label the different layers and describe the type of chemistry (and species) that occurs at each level. I do not know how to draw the diagram and what layers to include?

Nitrogen Content in Water

What method I could in a academic chemical laboratory to determine the nitrogen content in water? How could I then determine the quality of the water?