Recent content by winterwind

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    Moral & Legal Hazards of Accepting Poor School REUs

    Don't do it. Just tell them you need more time, then e-mail/call the other programs that you have not heard back from. Ask them for as much information as they have, such as if you are still in consideration, etc.
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    Schools REU and Graduate School (Mat Sci)

    1. Do the REU at X University. 2. Do good work and impress your PI. 3. Get letter of recommendation from PI at X University. 4. Apply to said university. 5. Profit?
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    Which Grad Program to Choose: Penn State or Penn?

    Go with Penn State. The financial situation pretty much seals the deal. Plus, Penn State is just as good as Penn in that field. The letter of recommendation from a department head shouldn't necessarily be of more value than one from another professor who can write a good letter on your behalf.
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    Help Needed: Deciding Between Summer Research Options

    Hi guys, I have an important decision to make in the next couple of days regarding my plans for the coming summer, and I would appreciate any input. I applied to the Amgen Scholar's Program, and have received an acceptance from UCSF. I'm interested in pursuing research in the area of chemical...
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    Can I Separate a Constant and Variable Expression in Exponential Manipulation?

    Unfortunately, that doesn't work, since the expression is eab. I would only be able to use that rule if it were eaeb. The constant a is multiplied to the variable b in the same exponential. The integral expression is: v3/[ev(h/kT) -1] where v is the variable, and (h/kT) is constant...
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    Can I Separate a Constant and Variable Expression in Exponential Manipulation?

    Homework Statement I am working on a problem, and there is a small step I need help on: I have the expression eab, where a is a constant, and b is a variable. I need to separate a and b so I can pull out the expression b from an integral expression. Is there any exponent law or manipulation...
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    Calculating the Freezing Point of Mercury Under Pressure

    Homework Statement The enthalpy of fusion of mercury is 2.292 kJ/mol, and its normal freezing point is 234.3 K with a change in molar volume of +0.517 cm/mol on melting. At what temperature will the bottom of a column of mercury (density 13.6 g /cm3) of height 10.0 m be expected to freeze...
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    Calculate Isothermal Compressibility of Van der Waals Gas

    Homework Statement Calculate the isothermal compressibility and the expansion coefficient of a van der Waals gas. Show, using Euler's chain relation that \kappaTR = \alpha(Vm - b). Homework Equations van der Waals equation virial expansion of state The Attempt at a Solution So I have to...
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    Isothermal reversible expansion

    Homework Statement Calculate the work done during the isothermal reversible expansion of a gas that satisfies the virial equation of state. Homework Equations Virial equation of state: pVm = RT(1+B/Vm + C/Vm + ...) Isothermal reversible expansion: w = -nRT ln(Vf/Vi) The Attempt at a...
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    Calculate \DeltarH0 and \DeltarU0 for Hydrogenation of Ethyne to Ethene at 348 K

    I just need help with this part of the probelem now: Calculate \DeltarU0 at 298 K for the hydrogenation of ethyne (acetylene) to ethene (ethylene) from the enthalpy of combustion and heat capacity data in Tables 2.5 and 2.7. Assume the heat capacaties to be constant over the temperature range...
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    Calculate \DeltarH0 and \DeltarU0 for Hydrogenation of Ethyne to Ethene at 348 K

    Homework Statement Calculate \DeltarH0 and \DeltarU0 at 348 K for the hydrogenation of ethyne (acetylene) to ethene (ethylene) from the enthalpy of combustion and heat capacity data in Tables 2.5 and 2.7. Assume the heat capacaties to be constant over the temperature range involved. \DeltafH0...
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    Virial expansion of van der Waals equation

    Homework Statement Express the van der Waals equation of state as a virial expansion in powers of 1/Vm and obtain expressions for B and C in terms of the parameters a and b. The expansion you will need is (1-x)-1 = 1 + x + x2 + ... Measurements on argon gave B = -2.17 cm3 mol-1 and C =...
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    Can Gas A or B be liquefied and do they have a critical temperature?

    Ok thanks guys. I am still wondering what conditions would allow the gas to liquefy. If temperature increases, yet pressure stays the same. Volume decreases, yet pressure stays the same. Are these conditions indicative of a gas being able to be liquefied? If so, how can I prove it...
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    Can Gas A or B be liquefied and do they have a critical temperature?

    Homework Statement The following equations of state are occasionally used for approximate calculations on gases: (gas A) pVm = RT(1+b/Vm), (gas B) p(Vm -b) = RT. Assuming that there were gases that actually obeyed these equations of state, would it be possible to liquefy either gas A or B...
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