# Search results

1. ### Quantum Chemistry/Mechanics Graduate Study

Hi all, I've been studying chemical engineering for three years now and will be entering my senior and final year next year. This year I found my quantum chemistry/mechanics course very interesting and enjoyable. I also found that I'm pretty good at it. I feel like I might be more...
2. ### Molar Volume and Molal Volume

The exact question I have to answer isn't about Molar and Molal volume but I need molal volume to plug into the equation for diffusivity coefficients. I have the molar volume of vitamin E 603cm^3/mol and its MW 430.7 and I need to find its molal volume cm^3/(g*mol) but I'm getting pretty...
3. ### Thermodynamics Entropy +2nd law problem

Homework Statement Propane at 350 degrees Celsius and 600cm^3 / mol is expanded in a turbine. The exhaust is atmospheric. What is the lowest possible exhaust temperature? How much work is obtained? You may assume ideal gas behavior and the heat transfer to the surroundings is negligible...
4. ### Thermodynamics Entropy question

Homework Statement A 10-kg block of copper is initially 100 degrees celsius. It is thrown into a very large lake that is 280K. What is the entropy change of the piece of copper. What is the entropy change of the universe? Homework Equations The Attempt at a Solution I know that...
5. ### Wronskian help

Homework Statement take the wronskian of [cos(theta)]^2 and 1+cos(2theta) Homework Equations The Attempt at a Solution so I set up the determinant [cos(theta)]^2 1+cos(2theta) as my y1 and y2 respectively and -2cos(theta)sin(theta) and -sin(2theta) as my y1 and y2 prime...
6. ### Thermodynamic pressure/temperature question

Homework Statement Consider filling a cylinder of compressed argon from a high-pressure supply line. Before filling, the cylinder contains 10 bar of argon at room temperature the valve is then opened, exposing the tank to a 50 bar line at room temperature until the cylinder reaches 50bar...
7. ### Quality and percent volume

Homework Statement A rigid container of volume 1 m^3 contains saturated water at 1MPa. If the quality is .10, what is the volume occupied by the vapor. Homework Equations The Attempt at a Solution I wanted to use the equation v=(1-x)(v_l)+x(v_v) where all v's are specific...
8. ### Boiling point on top of mount everest

Homework Statement At what temperature does water boil on the top of mount everest, elevation z = 8848m? Recall that the dependence of pressure with altitude is give by: P=P_atm * exp(-MWgz/RT) MW=molecular weight of the gas, P_atm =atmospheric pressure, g is the gravitational...
9. ### Confusion in Stoke's theorem!

Homework Statement Hello, this isn't a specific problem but a part I am confused about in Stoke's theorem. In my text the section on Line integrals (if C(t) is the parameterization of the curve) as the integral of F(C(t))*C'(t) but for vector fields the formula becomes the integral of...
10. ### Surface Integrals of Vector Fields question

Homework Statement F=<0,3,x^2> computer the surface integral over the hemisphere x^2 + y^2 + z^2 = 9 z greater than or equal to 0, outward pointing normal. Homework Equations The Attempt at a Solution I don't know why I keep getting this problem wrong. The general formula for...
11. ### Chemical vs biochemical engineering

Hey guys I have to choose between chemical and biochemical engineering soon as the two split paths after sophomore year...anyway...I don't really know much of the difference besides the classes. What I mean is...is there usually a large salary difference between the two? Can a biochem eng get...
12. ### Solenoid with a magnetic core

1. Homework Statement A long solenoid with 70.0 turns of wire per centimeter carries a current of 0.100 A. The wire that makes up the solenoid is wrapped around a solid core of silicon steel (Km=5200). (The wire of the solenoid is jacketed with an insulator so that none of the current flows...
13. ### Solenoid with a magnetic core problem

Homework Statement A long solenoid with 70.0 turns of wire per centimeter carries a current of 0.100 A. The wire that makes up the solenoid is wrapped around a solid core of silicon steel (Km=5200). (The wire of the solenoid is jacketed with an insulator so that none of the current flows...
14. ### Total magnetic field from two long parallel wires

Homework Statement Two long, straight, parallel wires, 10.0 cm apart carry equal 4.00-A currents in the same direction, as shown in the figure. ( in the figure the current carrying wires are at the end of a straight 10cm line and they are each in the direction coming out of the page)...
15. ### Organic chemistry determing nucleophile strength

this isn't exactly an specific question but a general one. I know that weak bases make good nucleophiles but how do I determine what bases are the weakest, what is weak enough to be considered a "good nucleophile" I'm a little confused please help thanks a lot!
16. ### Using a voltmeter

Homework Statement A circuit consists of a series combination of 6.00 -kOhm and 4.50 kOhm resistors connected across a 50.0-V battery having negligible internal resistance. You want to measure the true potential difference (that is, the potential difference without the meter present) across...
17. ### Organic chemistry SN1 reaction's

Homework Statement Find the major organic product B of http://www.webassign.net/userimages/kasandbe/CH221_ssii_02/CH221_exam2_ssii_02_7a.gif (with ethanol at 0 degrees Celsius) Homework Equations The Attempt at a Solution I thought that since it is a SN1 reaction the -OTs would...
18. ### Electric field from potential energy

Homework Statement Consider uniform electric field. The values of the potentials at the points(0,0) (.5,0) are equal and 20V higher than the potential at (0,.5) The magnitude and direction of the electric field are: a)0 b)40N/c j c)-40N/c j Homework Equations The Attempt...
19. ### Limits with three variables (a different problem)

Homework Statement the limit as (x,y)->0,0 of (x^2+y^2)ln(x^2+y^2) (Hint: as (x,y)->(0,0) r->0(from the right) Homework Equations The Attempt at a Solution I converted to polar coordinates then used trig identities and eventually got to the limit of r->0(from theright) of r^2...
20. ### Limits with three variables

Homework Statement lim as (x,y,z) ->0,0,0 of xyz/(x^2+y^2+z^2) it says (HINT: use spherical coordinates) Homework Equations The Attempt at a Solution I tried putting it in spherical coordinates but it didn't seem to help. I ended up getting...
21. ### Sphere with tangent plane

Homework Statement Find the equation of a sphere of radius 9 which is tangent to the plane x-2y+2z=4 and whose center lies on the x axis. b. Determine the point where the sphere is tangent to the plane. Homework Equations The Attempt at a Solution My TA told me it might be...
22. ### Potential Energy in a capacitor

A parallel-plate vacuum capacitor has 8.28 J of energy stored in it. The separation between the plates is 2.30 mm. If the separation is decreased to 1.00mm. What is the energy now stored if the capacitor was disconnected from the potential source before the separation of the plates was...
23. ### Find the inverse of y=x^3 + x +4

Homework Statement I'm helping my friend review for his exam in precalc and I can't seem to get this inverse. Find the inverse of y=x^3 + x +4 Homework Equations The Attempt at a Solution I switched the variables and then tried to isolate the y but I failed. I ended with...
24. ### Maclaurin series

Homework Statement find the maclaurin series of e^(3x) + e(-3x) Homework Equations The Attempt at a Solution I'm not sure about finding taylor and maclaurin series, I understand perfectly how to find the terms of the series...But how do I put it into a general term do I just...
25. ### Limit problem

Homework Statement find the limit as n->oo of n(ln(n+10)-ln(n)) Homework Equations The Attempt at a Solution the answer is 10 this is also part of my exam review I am pretty lost on this one I tried using log rules to combine the terms tried getting it in form for L'H but I...
26. ### Solving differential equations

[SOLVED] Solving differential equations Homework Statement Find the solution: dy/dx = (1+y^2)/(1+x^2) hint: there is a formula tan(a + b) that will simplify your answer. y(0)=1 Homework Equations The Attempt at a Solution I seperated the variables and integrated ending up with...
27. ### The National Society of Collegiate Scholars

I have been invited to join this organization the NSCS I'm wondering if any of you can provide insight, I have never really heard of them. I basically want to know if they are just trying to get money from college students or are they worth joining...? (They charge 75 dollars to join!) Being a...
28. ### Maclaurin Series

Homework Statement find the Maclaurin Series: f(x)=(e^x - cos(x))/x Homework Equations The Attempt at a Solution I'm not really sure what to do I do know the Maclaurin series of cos(x) I was thinking that using this known series then doing e^x - the known series then...
29. ### Programs Engineering Major looking for a minor

I'm a chemical engineering major in my freshman year, doing well in my classes. My schedule works out so that basically if I use all my electives towards either math or a humanities I only need 1 more class for a minor, I'm wondering what would be more beneficial to being an engineer a minor in...
30. ### Approximating Infinite Series

Homework Statement The infinite Series starts at n=1 and is (4-sin(n))/(n^2 + 1) For each series which converges, give an approximation of its su, together with an error estimate, as follows. First calculate the sum s_5 of the first 5 terms, Then estimate the "tail" which is the infinite...