All Matches

Solution Library

Expert Answer

Textbooks

Search Textbook questions, tutors and Books

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Tutors
Study Help
Ask a Question

Search
Sign In
Register

study help
engineering
chemical engineering

Questions and Answers of Chemical Engineering

Chelating ligands often form more stable complex ions than the corresponding monodentare ligands form with the same donor atoms. For example,where en is ethylenediamine and penten is The increased
Henry Taube, the 1983 Nobel Prize winner in chemistry, has studied the mechanisms of oxidation-reduction reac¬tions involving transition metal complexes. In one experi¬ment he and his
A compound related to acetylacetone is 1,1,1-trifluoro- acetylacetone (abbreviated Htfa):Htfa forms complexes in a manner similar to acetylacetone. Both Be2+ and Cu2+ form complexes with tfa-having
The equilibrium constant Ka for the reactionis 6.0 X 10-3.
Ethylenediamineterraacetate (EDTA4-) is used as a complexing agent in chemical analysis with the structure show in.
Hemoglobin (abbreviated Hb) is a protein that is responsible for the Transport of oxygen in the blood of mammals. Each hemoglobin molecule contains four iron atoms that serve as the binding sites for
Carbon monoxide is toxic because it binds more strongly to iron in hemoglobin (Hb) than does O2. Consider the following reactions and approximate standard free energy changes:
Qualitatively draw the crystal field splitting of the d-orbitals in a trigonal planar complex ion.
Consider the following complex ion, where A and B rep-resent ligands.The complex is known to be diamagnetic. Do A and B produce very similar or very different crystal fields? Explain.
Qualitatively draw the crystal field splitting for a trigonal bipyranudal complex ion.
Sketch and explain the most likely crystal field diagram for the following complex ion:NH?
Consider the following data:where en = ethylenediamine. b. Based on your answer to part a, which is the stronger oxidizing agent, Co3+ or Co(en)33+? c. Use the crystal field model to rationalize the
Consider the following complex ion where A and B repre-sent neutral ligands, and A produces a stronger crystal field than B.a. Draw an appropriate crystal field diagram for this complex ion (include
a. Calculate the molar solubility of AgBr in pure water. Ksp for AgBr is 5.0 X 10-13. b. Calculate the molar solubility of AgBr in 3.0 M NH3. The overall formation constant for Ag(NH3)2+ is 1.7 X
Sketch a d-orbital energy diagram for the following: a. A linear complex ion with ligands on the x axis b. A linear complex ion with ligands on the y axis
Define or illustrate the following terms. a. Thermodynamic stability b. Kinetic stability c. Radioactive decay d. β-particle production e. α-Particle production f. Positron production g. Electron
Which type of radioactive decay has the net effect of changing a neutron into a proton? Which type of decay has the net effect of turning a proton into a neutron?
Supply the missing particle, and state the type of decay for each of the following nuclear processes.a.b.
Write an equation describing the radioactive decay of each of the following nuclides.
Write balanced equations for each of the following processes. a. Chromium-51, which targets the spleen and is used as a tracer in studies of red blood cells, decays by electron capture. b.
In each of the following radioactive decay processes, supply the missing particle. a. 73Ga →73Ge + ? b. 192Pt → 188Os + ? c. 205Bi → 205Pb + ? d. 241Cm +? → 241Am e. 60Co → 60Ni + ? f. 97Tc
Write an equation describing the radioactive decay of each of the following nuclides. a. 68Ga (electron capture) b. 62Cu (positron) c. 212Fr (α) d. 129Sb (β)
One type of commercial smoke detector contains a minute amount of radioactive americium-241 (241Am), which decays by α-particle production. The α particles ionize molecules in the air, allowing it
The radioactive isotope 247Bk decays by a series of or-particle and β-particle productions, taking 247Bk through many transformations to end up as 207Pb. In the complete decay series, how many a
There are four stable isotopes of iron with mass numbers 54, 56, 57, and 58. There are also two radioactive isotopes: iron-53 and iron-59. Predict modes of decay for these two isotopes, and write a
The only stable isotope of fluorine is fluorine-19. Predict possible modes of decay for fluorine-21, fluorine-18, and fluorine-17.
Predict whether each of the following nuclides is stable or unstable (radioactive). If the nuclide is unstable, predict rhe type of radioactivity you would expect it to exhibit. a. 4519K b. 5626Fe c.
Many elements have been synthesized by bombarding relatively heavy atoms with high-energy particles in particle accelerators. Complete the following nuclear reactions, which have been used to
Americium-241 is widely used in smoke detectors. The radiation released by this element ionizes particles that are then detected by a charged-particle collector. The half-life of 241Am is 433 years,
Krypton consists of several radioactive isotopes, some of which are listed in the following table. Isotope .... Half-life Kr-73 ...... 27s Kr-74 ...... 11.5 min Kr-76
Radioactive copper-64 decays with a half-life of 12.8 days. a. What is the value of k in s-1? b. A sample contains 28.0 mg 64Cu. How many decay events will be produced in the first second? Assume
The curie (Ci) is a commonly used unit for measuring nuclear radioactivity: 1 curie of radiation is equal to 3.7 X 1010 decay events per second. a. What mass of Na238SO4 has an activity of 10.0 mCi?
The first atomic explosion was detonated in the desert north of Alamogordo, New Mexico, on July 16, 1945. What percentage of the strontium-90 originally produced by that explosion still remains as of
Iodine-131 is used in the diagnosis and treatment of thyroid disease and has a half-life of 8.0 days. If a patient with thyroid disease consumes a sample of Na131I containing 10. µg of 134I, how
Phosphorus-32 is a commonly used radioactive nuclide in biochemical research, particularly in studies of nucleic acids. The half-life of phosphorus-32 is 14.3 days. What mass of phosphorus-32 is left
A chemist wishing to do an experiment requiring 47Ca2+ (half-life = 4.5 days) needs 5.0 µg of the nuclide. What mass of 47CaCO3 must be ordered if it takes 48 h for delivery from the supplier?
Explain the theory behind carbon-14 dating. What assumptions must be made and what problems arise when using carbon-14 dating?
The decay of uranium-238 to lead-206 is also used to estimate the age of objects. Specifically, 206Pb-to-238U ratios allow dating of rocks. Why is the 238U decay to 206Pb useful for dating rocks but
At a flea market you’ve found a very interesting painting done in the style of Rembrandt’s “Dark Period”. You suspect that you really do nor have a genuine Rembrandt, so you take it to the
A living plant contains about the same fraction of carbon-14 as atmospheric carbon dioxide. The observed rate of decay of carbon-14 from a living plant is 15.3 counts per minute per gram of carbon.
During World War II, tritium (3H) was a component of fluorescent watch dials and hands. Assume you have such a watch that was made in January 1944. If 17% or more of the original tritium was needed
A proposed system for storing nuclear wastes involves storing the radioactive material in caves or deep mine shafts. One of the most toxic nuclides that must be disposed of is plutonium-239, which is
A rock contains 0.688 mg of 206Pb for every 1.000 mg of 238U present. Assuming that no lead was originally present, that all the 206Pb formed over the years has remained in the rock, and that the
The mass ratios of 40Ar to 40K can also be used to date geological materials. Potassium-40 decays by two processes:a. Why are 40Ar/40K ratios rather than 40Ca/40K ratios used to date materials? b.
The sun radiates 3.9 X 1023 J of energy into space even’ second. What is the rate at w’hich mass is lost from the sun?
The earth receives 1.8 X 1014 kj/s of solar energy. W'hat mass of solar material is converted to energy over a 24-h period to provide the daily amount of solar energy to the earth? What mass of coal
The most stable nucleus in terms of binding energy per nucleon is 56Fe. If the atomic mass of 56Fe is 55.9349 amu, calculate the bind mg energy per nucleon for 56Fe.
Calculate the binding energy per nucleon for 21H and 31H. The atomic masses are 21H, 2.01410 amu, and 31H, 3.01605 amu.
Calculate the binding energy in J/nucleon for carbon-12 (atomic mass 12.00000) and uranium-235 (atomic mass 235.0439). The atomic mass of 11H is 1.00782 amu, and the mass of a neutron is 1.00866 amu.
The mass defect for a lithium-6 nucleus is —0.03434 g/mol. Calculate the atomic mass of lirhium-6.
The binding energy per nucleon for magnesium-27 is 1.326 X 10-12 J/nucleon. Calculate the atomic mass of magnesium-27.
A positron and an electron annihilate each other upon colliding, thereby producing energy:Assuming that both y rays have the same energy, calculate the wavelength of the electromagnetic radiation
The easiest fusion reaction to initiate isCalculate the energy released per nucleus of 42He produced and per mole of 42He produced. The atomic masses are as follows: 21H, 2.01410 amu; 31H, 3.01605
Calculate the amount of energy released per gram of hydrogen nuclei reacted for the following reaction. The atomic masses are 11H, 1.00782 amu, and 21H, 2.01410 amu.
The typical response of a Geiger-Miiller tube is shown below. Explain the shape of this curve.
Define fission and fusion. Fusion processes are more likely to occur for lighter elements, whereas fission processes are more likely to occur for heavier elements. Explain.
Why are elevated temperatures necessary to initiate fusion reactions but not fission reactions?
Much of the research on controlled fusion focuses on the problem of how to contain the reacting material. Magnetic fields appear to be the most promising mode of containment. Why is containment such
During the research that led to production of the two atomic bombs used against Japan in World War II, differ ent mechanisms for obtaining a supercritical mass of fissionable material were
There is a trend in the United States toward using coal-fired power plants to generate electricity rather than building new nuclear fission power plants. Is the use of coal-fired power plants without
Consider the following reaction to produce methyl acetate:When this reaction is carried out with CH3OH containing radioactive oxygen-18, the water produced is not radioactive. Explain.
Radiotracers are used in the medical sciences to learn about metabolic pathways. What are radiotracers? Explain why 14C and 32P radioactive nuclides would be very helpful in learning about metabolic
The biological effects of a particular source of radiation depend on several factors. List some of these factors. Even though 85Kr and 90Sr are both β-particle emitters, the dangers associated with
Although y rays are far more penetrating than a particles, the latter are more likely to cause damage to an organism. Why? Which type of radiation is more effective at promoting the ionization of
Consider the following information: i. The layer of dead skin on our bodies is sufficient to protect us from most α-particle radiation. ii. Plutonium is an α-particle producer. iii. The chemistry
Consider the following graph of binding energy per nucleon as a function of mass number.a. What does this graph tell us about the relative halflives of the nuclides? Explain your answer. b. Which
The mass percent of carbon in a typical human is 18%, and the mass percent of 14C in natural carbon is 1.6 X 10-10%. Assuming a 180-lb person, how many decay events per second occur in this person
Using the kinetic molecular theory, calculate the root mean square velocity and the average kinetic energy of 21H nuclei at a temperature of 4 X 107 K.
A small atomic bomb releases energy equivalent to the detonation of 20,000 tons of TNT; a ton of TNT releases 4 X 109 J of energy when exploded. Using 2 X 1013 J/mol as the energy released by fission
When nuclei undergo nuclear transformations, y rays of characteristic frequencies are observed. How does this fact, along with other information in the chapter on nuclear stability, suggest that a
A chemist studied the reaction mechanism for the reactionby reacting N16O with 18O2. If the reaction mechanism is What distribution of l8O would you expect in the NO2? Assume that N is the central
Define “third-life” in a similar way to “half-life,” and determine the “third-life” for a nuclide that has a half-life of 31.4 years.
In addition to the process described in the text, a second process called the carbon-nitrogen cycle occurs in the sun:a. What is the catalyst in the above scheme? b. What nucleons are
Naturally occurring uranium is composed mostly of 238U and 235U, with relative abundances of 99.28% and 0.72%, respectively. The half-life for 238U is 4.5 X 109 years, and the half-life for is 7.1 X
The curie (Ci) is a commonly used unit for measuring nuclear radioactivity: 1 curie of radiation is equal to 3.7 X 1010 decay events per second. A 1.7-mL sample of w’ater containing tritium was
Estimate the temperature needed to achieve the fusion of deuterium to make an α particle. The energy required can be estimated from Coulomb’s law.
Radioactive cobalt-60 is used to study defects in vitamin B12 absorption because cobalt is the metallic atom at the center of the vitamin B12 molecule. The nuclear synthesis of this cobalt isotope
The most significant source of natural radiation is radon-222. 222Rn, a decay product of 238U, is continuously generated in the earth’s crust allowing gaseous Rn to seep into the basements of
For uranium to be useful as a nuclear fuel, the relative amount of 235U to 238U must be increased from about 0.7% 235U in naturally occurring uranium to about 3%. The process of gas diffusion
Zirconium is one of the few metals that retains its structural integrity upon exposure to radiation. The fuel rods in most nuclear reactors therefore are often made of zirconium. Answer the following
What is long-run economic growth, and how is it measured? Have all countries experienced about the same amount of long-run economic growth? Briefly explain.
In an article in the Economist magazine, a survey on expectations about standards of living yielded the following conclusion: “Half thought the next generation would have a lower standard of
According to the study cited in the chapter opener, “Increasing evidence suggests that even short [recessions] can have substantial effects on workers’ careers.”Why might graduating into a weak
What is a business cycle? How is the unemployment rate measured? How has the unemployment rate varied over time in the United States? Do most high-income countries experience about the same average
Describe the average inflation rate in the United States over the past 40 years. When has there been high inflation? When has there been deflation? Are inflation rates roughly the same in countries
How has the severity of the business cycle varied over time in the United States? What is the Great Moderation?
What is monetary policy? What is fiscal policy? How are they different?
How might you identify how “open” an economy is? Is international trade more or less important to the United States than to many other countries?
The average rate of growth of U.S. real GDP is approximately 3%, as measured over long periods of time. China has been averaging growth rates that are considerably higher than this for much of the
Consider the following statement: “A country like the United States is more open than a country like Belgium because it is larger and has a higher total value of imports and exports.” Do you
Why do economists build models?
Bryan Caplan of George Mason University and Stephen Miller ofWestern Carolina University argue that there is substantial evidence that: “Economists and the general public have systematically
Explain the steps generally used in building an economic model.
Many people believe that significant numbers of U.S. jobs have been “outsourced”; that is, firms have relocated operations to countries in which labor is cheaper, so the jobs have moved overseas.
Explain which of the following statements would make a reasonable hypothesis to test. Use the concepts of normative and positive statements in your answers. a. Increases in the duration of
Consider the following statement: “Economic models use many simplifying assumptions. Thus they do not apply to the more complex events in the real world.” Do you agree or disagree with this
What is GDP? In what ways is it both a measure of total production and a measure of total income?
Consider the following statement: “The BEA revises GDP data several times. Since preliminary estimates of GDP are likely to be incorrect, they should not be used for policymaking.” Explain
According to financial journalist Roger Lowenstein writing in the New York Times, “The budgetary math is irrefutable: generous [public employee] pensions end up draining money from schools, social
Why are intermediate goods not counted in GDP? What is an imputed value, and which types of goods and services are measured using imputed values?

Showing 2500 - 2600 of 6781

First
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
Last

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Campus Ambassador

Company Info

Security
Copyrights
Privacy Policy
Terms & Condition
SolutionInn Fee
Scholarship

Services

Sitemap
Fun
Definitions
Become Tutor
Study Help Categories
Recent Questions
Expert Questions

Copyright © 2024 SolutionInn All Rights Reserved.

Get the SolutionInn - Study Help App