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1. ### Determining SN1/SN2 Balance for 2-Bromobutane Formation

For example, if we have 2-butanol, a compound with a secondary \alpha carbon and I reacted this with HCl and NH4Br I would get 2-bromobutane (via nucleophillic substitution), but how would I determine whether this goes via SN1 or SN2 to achieve this? Now, if this was 1-bromobutane, I know...
2. ### Concept question on using integrals to find displacement

Homework Statement I was reading a solution to the following question: Given v(t) = 22 + 18 t, use calculus to determine the total displacement from t initial= 1.5 s to t final = 3.1 s Homework Equations Here are the steps in the equation...
3. ### Having a massive brain fart SIMPLE molarity -> molality conversion

Having a massive brain fart... SIMPLE "molarity -> molality" conversion... This isn't even a homework question per se, I'm just trying to understand how the question converted the molarity to the molality value, via the density given. I just got a different value of molality when trying to...
4. ### How do you see the sun after it has set?

How do you see the sun after it has set?? Homework Statement The density of the atmosphere decreases with height, as does the index of refraction. Explain how one can see the sun after it has set. Homework Equations Snell's Law: sin x1 * x1 = sin x2 * x2 The Attempt at a...
5. ### Ridiculously simple acceleration and velocity vectors, but I can't get them

Ridiculously simple acceleration and velocity vectors, but I can't get them... We're supposed to answer a series of questions based on this diagram, but I am so confused by the answers. Homework Statement A car travels at constant speed along the curved path shown in the figure below...
6. ### Higher Chemical Concentration = Higher Temperature of Precipitation. Why?

If two chemicals are mixed together, say: Na_2SO_4 + CaCl_2 --> 2NaCl + CaSO_4 If I had varying concentrations of the reactant solutions, why is it that the higher concentration mixtures will precipitate at a higher temperature? and lower concentration chemicals will precipitate at a lower...
7. ### Figuring Out Enthalpy Changes in High School Chemistry Labs

Well, my chemistry teacher is extremely confusing, and wants us to create our own lab where we figure out the enthalpy changes in a chemical reaction. Is there are reaction out there that would give a considerable change in temperature, while using chemicals typically found in a high school? As...
8. ### A simple circle question

interesting, i was thinking that: Line OM + r = R would that work?
9. ### A simple circle question

Hi guys, I found this little problem on some website ages go, and was just wondering what you think of it: http://img354.imageshack.us/img354/9052/cirlce8hk.gif [Broken] Anyone have any ideas?
10. ### Graphs: End Behavoir Question

Hi I've got a little question regarding the end bevhoir of this graph, x/(x^2-4) http://img20.imageshack.us/img20/5609/end7ht.jpg [Broken] I think that determining the end behavoir is in relation to the x axis. So would the end bevhoir of the graph be from negative to postitive? (-/+)...
11. ### Simple Trig Question Help

at risk of sounding stupid, what's second quadrant? edit: ok, i think i might need to show the full question, as this is a multiple choice question.. What is the value of cos A if sin A = 0.9063 and angle A is an obtuse angle? A. -0.4226 B. -0.0158 C. 0.0158 D. 0.4226
12. ### Simple Trig Question Help

hmm.. I am not sure what the pythagrean identies are... and i haven't learned about them either.. is there a simpler way to do this?
13. ### Simple Trig Question Help

What is the value of cos A if sin A = 0.9063 and angle A is an obtuse angle? Does this need the sine or cosine laws? What would the obtuse angle thing be hinting at? Any help would be appreciated!
14. ### A perfect square trinomial stumped.

Ah! Thank You Guys! I see how it works now! :rolleyes:
15. ### A perfect square trinomial stumped.

ok, I'm pretty sure this is ridiculously simple, but I am stumped by this question.. What value of k would make 25x^2 - 60xy + ky^2 a perfect square trinomial? I just don't know where to begin in order to find k. :uhh: Any help would be much appreciated!

anyone? :/
17. ### Factor(s) that affect percent yield

Hi everyone, For a science lab, I am asked to find the following: What factor(s) affect percent yield in a reaction which produces calcium carbonate? We are given a selection of chemicals to use to get the CaCl_2 but I have chosen the following: CaCl_2 + Na_2CO_3 --> CaCO_3 + 2NaCl...
18. ### Charge on Nuclei of Mg, Ne, K^+, S^2-

I've got this following question which I don't really get: What is the charge on the nucleus of each of the following? (assuming they are neutral) a) Mg b) Ne c) K^+ d) S^2- What I don't understand is the definition of "charge on the nucleus" I am assuming that only protons have...
19. ### Charge on the nucleus

I've got this following question which I don't really get: What is the charge on the nucleus of each of the following? (assuming they are neutral) a) Mg b) Ne c) K^+ d) S^2- What I don't understand is the definition of "charge on the nucleus" I am assuming that only protons...
20. ### Best way to determine the weight/volume of a grain of sand/salt

I'm not looking into anyone giving me any answers here, but I just want to gather some ideas for a lab that requires me to calculate the volume and wieght (therefore, finding the density) of a grain of salt and sand. I've thought about the idea of counting out 100 grains and then weighing...