Homework Statement
There are 2 versions of the problem that I've heard:
A bucket on wheels is moving at a constant velocity on a frictionless surface. It's raining out so the bucket is gaining mass. Will it slow down, speed up, or remain at that velocity as it gains mass?
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Homework Statement
I haven't been assigned these questions, but I'm trying to trudge through them to better understand symmetry. This is for my inorganic class.
It's just a series of short questions like:
C3 – S56 = ?
S4 + i = ?
C3 + i = ?
Stuff like this. And just looking at the...
Actually, the two methods don't give me the same answer. If I use wC = -(wA + wB), I get wC = 458.027 kJ, and q = ΔU - w = -227.683 kJ.
If I take ΔU of the entire system to be qC, then I get -1143.737 kJ. I'm not sure, but why would w = 0 for the entire system?
EDIT: I just re-calculated it...
Ah, sorry, for the first one I meant q = ΔU - wC = ΔU - [- (wA + wB)].
For the second, his rationale is that you can take the process stepwise, and calculate the q for first the isothermal, reversible expansion (q = nRT ln (Vf/Vi), where T = 300 K), and then calculate q for the isochoric...
Because of the autoprotolysis of water? So we'd use Kw = 1 x 10–14 to get OH- in terms of H3O+, correct? But this doesn't change the pH by an appreciable amount does it?
One thing I was struggling with was how to factor the 0.1 M contribution of the OH- into the charge balance. Does the right...
So, it wouldn't be correct to use q = nRT ln (Vf/Vi) + n \int_{700}^{300} \bar{C_{v}}dT? That's what my friend thinks is correct; essentially it's the same way we found ΔS, but we aren't dividing by T, because ΔS = q/T.
Wouldn't there be expansion work against volume in chamber B and A that...
Yes, you're correct of course. I noticed that later on but forgot to edit it in. Also, I believe my mass balance neglected [H3PO4]. But the pH of 7.3 was after correcting for these. Oddly enough, I got around 10 after adding NaOH, however my friend got 12; not particularly sure why.
Also...
Homework Statement
In a 3-chambered system, separated by 2 pistons, all of the walls are adiabatic, except for the wall on the outside of chamber C (the wall marked }).
[A | B | C}
The pistons are frictionless, the gas fills all 3 chambers and is ideal, and \bar{} = R. Total volume = 12...
Yeah, I know there's going to be very little [PO43-], but our prof wants us to calculate it as if there will be. And yeah, he does want it done the long way. It's a terrible equation, but wolfram alpha helped me get the final answer, which, if I did everything right, should be about 7.351.
Homework Statement
8.9985 g of Na2HPO4 and 4.0211 g of NaH2PO4 * 7 H2O are added to 1 L of 0.20 M KCl in water. KCl does not participate in any way but to maintain ionic strength, at 0.20 M.
H3PO4 (aq) + H2O → H2PO4- (aq) + H3O+, Ka1 = 7.11 x 10-3
Ka2 = 6.32 x 10-8
Ka3 = 7.1 x 10-13
(a)...
That was the equation that I ended up using when I revised my answer. In the end, I got that at 100 K, ΔG = –68.6 kJ. Our professor also had us approximate the value using the Gibbs-Helmholtz equation, which gave me –72.6 kJ. It makes sense for the two values to be off, because I know the...
Homework Statement
"Estimate the standard reaction Gibbs energy of the following reaction:
N2 + 3 H2 ‒‒> 2 NH3
at 100K and at 1000K."
Homework Equations
ΔS(T2) = S°(T1) + ∫ n Cp dT/T
ΔG = ΔH ‒ TΔS
Given data: http://imgur.com/MBakUEB (may need to right-click and select...
So I've been slowly plodding through this problem, and so far this is what I've done:
Took partial of ##x##, factored out the ##e## term and canceled it, because it can never equal ##0##.
So ##x^2+4y^2-1 = 0##
Same with the partial of ##y##: ##x^2+4y^2 = 4##
Now, these are ellipses...
Homework Statement
Consider the function f(x,y) = (x2 + 4y2)e(1-x2-y2)
Find all critical points, and identify them as maxima, minima, or saddle points.
The Attempt at a Solution
I took the partial of x and the partial of y, and set them equal to 0. This is what I got:
fx(x,y) =...
Homework Statement
Predict the major organic product of the following reactions:
The Attempt at a Solution
For 1, I got:
And for 2, I got:
If anyone can help confirm, I'd be much obliged! Our professor is crazy and gives these types of problems for practice...