Recent content by Youngster

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    Calculating Equilibrium Pressures

    Homework Statement For the reaction 2 NO_{2}(g) \leftrightarrow N_{2}O_{4}(g) ΔH°_{rxn} = -57.2 kJ and ΔS°_{rxn} = -175.8 J/K A 1 L container is initially filled with 1 atm of NO_{2} at 298 K. Find the equilibrium pressures of NO_{2} and N_{2}O_{4} at 298 K if a. volume is held...
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    Calculation of Helmholtz energy

    -\int\frac{1}{x} I understand - From 20L to 40L, the later term should have the difference \frac{1}{V_{2}} - \frac{1}{V_{1}} multiplied by an^{2}
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    Calculation of Helmholtz energy

    Yep! This was actually a very DOH! moment for me. So I forgot that I can just plug in the equation of state and write P in terms of V. This leads to the differential equation: -\intdA = \int\frac{nRT}{V}-\frac{an^{2}}{v^{2}}dV, from 20L to 40L This comes out as nRT...
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    Calculation of Helmholtz energy

    Homework Statement The 4 fundamental equations of thermodynamics are: dE = TdS - PdV dH = TdS + VdP dG = VdP - SdT dA = - PdV - SdT Supose a gas obeys the equation of state P = \frac{nRT}{V} - \frac{an^{2}}{V^{2}} Use one of the fundamental equations to find the change in Helmholtz energy...
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    What is the identity of the monoamine monocarboxylic amino acid?

    Ah, yes. I apologize for that. I'll be more specific next time. This is a made up problem that goes along with a lab assignment. To elaborate, the 0.2 N HCl information goes along with my titration curve below: As far as I know, the actual amino acid unknown solution was prepared...
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    What is the identity of the monoamine monocarboxylic amino acid?

    Sorry, it seems the 0.2 N HCl information only applies to my actual lab data. The question above is what I assume to be a practice calculation to be done with my lab data
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    What is the identity of the monoamine monocarboxylic amino acid?

    Alright well, I've tried something else. Starting with the equation for the reaction: H2X + 2NaOH → Na2X + 2H2O Where X is the amino acid. The equation states that 2 moles of base titrates 1 mole of amino acid. Assuming the change from pH 0.8 to pH 12.0 is the full titration (meaning the both...
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    What is the identity of the monoamine monocarboxylic amino acid?

    I probably should have specified that. The amino acid was dissolved in 0.2 N HCl. So the amine group is probably protonated, and the overall charge is +1 No. It should have at least two titratable groups
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    What is the identity of the monoamine monocarboxylic amino acid?

    Homework Statement 7.39 mmol of base was used when titrating 432 mg of a monoamine monocarboxylic amino acid from pH 0.8 to 12.0. What is the name of the amino acid? Homework Equations None I suppose. Henderson-Hasselbalch perhaps, but I don't see how that helps me The Attempt at...
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    Calculating Thermodynamic Heat and Work

    Ah yes, thank you. I have one more item I'd like to clarify. I have two equation for thermodynamic work listed in my notes. 1. w = -∫PdV 2. w = -nRT ln\frac{V_{2}}{V_{2}} I used the first equation to obtain -1013J, but the second equation provides a different value of -987.7J. This...
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    Calculating Thermodynamic Heat and Work

    Okay, so what I'm getting is that since it's an isothermal process, the change in internal energy is 0. That would mean q is just the reverse of w. Does this sound right? That would mean this is reversible too, yes?
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    Calculating Thermodynamic Heat and Work

    Homework Statement One mole of ideal gas expands isothermally at 20°C against a constant pressure of 1 atm from 20 to 30L. (1 atm = 1.013 x 105Pa; 1 m3 = 1000L Find q, w, ΔE, and ΔH in Joules Homework Equations ΔE = q + w w = -\intPdV H = E + PV The Attempt at a Solution I solved for work...
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    How to Integrate Partial Fraction Problems without a Prefix

    Ah, I see now. It's been a while since I've done that, but it works. I suppose I should do similar exercises to get this in my head. And yeah, part of the integral turned out to be an inverse tangent one. Thanks a lot.
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    How to Integrate Partial Fraction Problems without a Prefix

    Homework Statement \int\frac{8x^{2}+5x+8}{x^{3}-1} Homework Equations Because the denominator can be reduced to (x-1)(x^{2}+x+1), I set up the partial fractions to be \frac{A}{(x-1)} + \frac{Bx+C}{(x^{2}+x+1)} The Attempt at a Solution I've solved for A, B, and C, and now have...
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    Trig Integral sin^2 x + cos^2 x = 1

    -\frac{1}{6}cos^{6}x + \frac{1}{2}cos^{4}x - \frac{1}{2}cos^{2}x + C I think I was missing that negative. Is this correct?
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