# Search results

1. ### Born Theory - Finding the value of Z (solvation of ions)

1. Homework Statement What's the energy for transfer from ε=1 to water with r=2.5Å ε=1 to water with r=5Å. 2. Homework Equations ΔG = (1/2)*(Z^2/r)*[(1/e1)-(1/e2)] 3. The Attempt at a Solution ΔG = (1/2)*(Z^2/2.5)*[(1/80)-(1/1)] However, I am stuck on the Z variable...
2. ### Calculate osmolality of a 0.1% and a 0.9% NaCl.?

I tried to calculate the osmolality (mOsm/kg) of a 0.1% and a 0.9% NaCl solution but I am not sure I'm doing this right. First I calculated the NaCl grams in a liter of solution, so for 0.1% I have 0.01g of NaCl. Then I divided by the 58.44 (MW) to get moles. Then I divided the moles by 1...
3. ### Help calculating a diffusion rate using Fick's equation.

1. Homework Statement Assuming: Organism weight = 25 g Organism lenght = 30 cm [Na+ (ECF)] = 200 mM [Na+ (water)] = 500 mM ΔX(gill) = 6 μm ΔX(skin) = 25 μm A(gill) = 5.0 cm^2/gm A(skin) = 10 cm^2/gm Dk(gill) = 2 X 10^4 cm^2/s Dk(skin) = 1 X 10^4 cm^2/s Calculate the Na+...
4. ### How to choose plasmids for certain types of cell?

How do you know which plasmids are suitable (disregard the efficiency for now) for say, mammalian cells? For example, this http://www.addgene.org/12091/" [Broken] is it suitable for HeLa cells? Basically, I'm confused as to what "Growth strain" and "Vector type" mean. Does Growth strain mean...
5. ### RHR for Magnetic fields, why is it design in such a way?

I don't feel like this is a homework question, more like a curiosity question. If I'm wrong then feel free to move it to the homework section and my apologies. I know how the RHR works for magnetic forces and I can apply it with no problem, however I'm not a physics major so maybe I'm missing...
6. ### Raoult's law - Vapor pressure

The density of toluene is 0.862g/ml at 25C and it's vapor pressure s 28.44 mmHg. At 25C, the vapor pressure of toluene above a solution of C10H8 in 500ml toluene is 27.92 mmHg. How many grams of C10H8 are present in the solution? I first used Raoult's equation to find X. Then I used the...
7. ### Would exonic primers affect gDNA amplification?

Will a primer designed for an exonic sequence anneal and sucessfully amplify a gDNA strand? I'm having trouble amplifying gDNA using that primer. cDNA with that primer amplifies perfectly. I have no problem amplifying gDNA using another primer that anneals to intronic sequences.
8. ### What kind of errors would be produced by excess taq in PCR?

What kind of errors would be produced by "excess" taq in PCR? Not sure if this belong in the Homework section. Put it here since it's not homework. What kind of errors will I get by adding 6.75µL taq pol to +50µL of cDNA? The master mix will be added to the cDNA resulting in an excess of taq...
9. ### Term Paper: Is the brain immunologically privileged?

Term Paper: "Is the brain immunologically privileged?" I have to write a term paper for my neuroscience class and the theme is "Is the brain immunologically privileged?". According to my professor I have a pretty nice introduction that explains the anatomical aspects of the brain that makes it...
10. ### HH Equation to calculate [HCO3-]

I'm given the following values: pH = 7.48, PO2 = 120mmHg, and PCO2 = 18mmHg. I have to find the [HCO3] using these values. There's one thing I don't understand about the Henderson-Hasselbalch equation and that is how to calculate the [CO2]. I found out that [CO2] = 0.03*PCO2. My question is...
11. ### Intro to Neuroscience

I need a little help with this assignment from my neuroscience class. I have tried to answer them but I'll like to know if my reasoning is right or wrong. I had to use the Neurons in Action software at school for some simulations but I think most of the questions could be answered without it...