Recent content by leumas614

I did an equilibrium calculation with some chem software that I have and it told me that a syngas reaction CH4+0.5O2\rightarrow 2H_{2}+CO which is an exothermic reaction will proceed to completion at high temperature. If you increase temperature, that should drive the reaction backwards...

Keq is equal to e^{-\frac{\Delta G}{RT}}. Just find \Delta G by using a table of thermodynamic data.

Can anyone please explain the stress fields in cylindrical coordinates? What is the difference between \sigma_{rz} and \sigma_{\theta z}? What is the difference between stress in the r axis and stress in the \theta axis? Thanks

http://en.wikipedia.org/wiki/Getting_the_wind_knocked_out_of_you

at the graduate level the differences become blurred. Many ChemE's do more materials research and many MatSci's do more ChemE research. They are very similar when it comes to research

yes.

ok, I got it. I asked the TA and he said the key relationship that I was missing is this: \frac{dn}{dt}=n\frac{Sp}{V} The units work out. So I worked it out from there. What you can do then is say U=H_{out}n_{out} since H_{in}n_{in} is zero because there is no mass flowing into...

I still don't quite follow what you're suggesting. The volume does not change because we took the system to be the inside of the chamber which is rigid. Using dV/dt would only work if the chamber was not rigid. But then if the volumetric flow rate is not the molar flow rate than it has no...

But this is what I don't understand. The volumetric flow rate is not constant because the tank is draining so presumably the amount of molecules flowing out of the tank is changing with time. So I don't know what the volumetric flow rate is. I understood the Sp in the question to mean, it...

You get Cv\frac{V}{R}\frac{dP}{dt}=\frac{dU}{dt} So we can relate U with P but you still don't have an expression for P so only one equation with two unknowns. You can't replace P with an expression for T because T is also unknown. Here's what I did. dU=d(Hn) but both H and n are...

Yes, I took the time derivative of PV=nRT holding V constant. V \left(\frac{dP}{dt}\right)=R\left(T \frac{dn}{dt}+n \frac{dT}{dt}\right) dU=nCvdT \frac{dU}{dt}=Cv\left(n\frac{dT}{dt}+T\frac{dn}{dt}\right) from energy balance, dU=Hdn integrating gets U=Hn which equals U=(U+PV)n...

Can anyone please help me with this problem? Consider the act of evacuating a chamber with a vacuum pump. Vacuum pumping rates are usually given in volumetric pumping speeds, Sp, whose units are typically volume/unit time, e.g., 1 m3/min. In other words, the number of molecules in 1 m3 at...

I recommend doing a search on the site. There should be tons of threads about this.

I would imagine that Civil and MechE has some chemistry if you're dealing with structures but many times this is incorporated into a general Materials Science requirement. For the most part, the chemistry that you need to know is covered in your other courses. The requirement of one semester...

What is a one-boy family? How can there be girls in a one-boy family?