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LongLiveLife

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Because it is an alcohol. Where the -OH group in electrolytes is ionically bonded to the cation, the C-O bond (in an alcohol and any other organic compound really) is covalent and is thus incapable of dissociation.

[EDIT] Oops, I forgot to say: add H2O(l) to both sides of the equation for all the equations I gave. (I am unsure how pedantic your professors are.)
 

Dogenzaka

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Wait, so you mean for the dissociation equation, I have to put
NaCl + H20 -> NaCl
H20 + H20 <-> H20

?

It says "Equation for dissociation (use -> for strong electrolytes and <-> for weak electrolytes)" but I really have no idea what it's asking me to do.
 

LongLiveLife

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NaCl(s) + H2O(l) -> Na+(aq) + Cl-(aq) + H2O(l) | STRONG
CaCl2(s) + H2O(l) -> Ca2+(aq) + 2CL-(aq) + H2O(l) | STRONG
CH3COOH(?) + H2O(l) <-> CH3COO-(aq) + H+(aq) + H2O(l) | WEAK (use the equilibrium sign for this.)
HCl(g) + H2O(l) -> H+(aq) + Cl-(aq) + H2O(l) | STRONG
CH3OH | NOT AN ELECTROLYTE
Distilled water | NOT AN ELECTROLYTE
Tap water | WEAK ELECTROLYTIC PROPERTIES (because of the dissolved mineral ions.)



Done.

I'm iffy on the "+ H2O(l)" on the right hand side of the equation because it cancels with the one on the left; but in my mind, you need water to initiate the dissociation, and if there are 2H's and an O on the left hand side, you will need 2H's and an O on the right. However, different professors will tell you different things, so take your professor's advice over mine on that detail.
 

Dogenzaka

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Okay. Well I won't get to ask my professor....that's just my lab TA and he's kind of a douche and doesn't really explain anything or answer questions; he just takes up these worksheets every week for a lab grade :l

Thanks for the help. I appreciate it. Our lecture notes covered electrolytes, but only said "Uhhhh, acids and bases are strong electrolytes....and salts...and stuff"....so it really didn't help us that much for this. Lol.
 

LongLiveLife

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Okay. Well I won't get to ask my professor....that's just my lab TA and he's kind of a douche and doesn't really explain anything or answer questions; he just takes up these worksheets every week for a lab grade :l

That's too bad. I did some searching, and Google suggests that you omit the H2O entirely. But it also suggests you remove the state symbols, which irks me. I say just put it in. Give 'em more than they can handle.

Thanks for the help. I appreciate it. Our lecture notes covered electrolytes, but only said "Uhhhh, acids and bases are strong electrolytes....and salts...and stuff"....so it really didn't help us that much for this. Lol.

No problem! It was my pleasure. A rule of thumb: any compound involving cations from Groups I and II of the periodic table are strong electrolytes, but the reverse is true for organic compounds -- they generally exhibit poor dissociation because of the strong covalent bonds throughout.
 

Nostalgia

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Is anyone here really good at physics? I have a few problems here that I need help with. I'd really appreciate it.
 

Nostalgia

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The section is on forces, but I'm not sure if this particular question utilizes them. Here's the first one. A 7.6 kg ball is hanging from a cord inside a car when it's at rest. It suddenly starts to accelerate, and the cord is jerked back at a 35° angle. It asks to find the acceleration of the car. I'd rather not have the answer. I just need help with carrying out the procedure. If you need a pic, let me know.

Oh, and the hint that it gives is that the acceleration of the ball equals the acceleration of the car.

I had assumed that since 'a' downward is 9.8 m/s^2, I should set tan35° = opp/9.8, where opp = the acceleration of the ball parallel, and therefore, equal to the car, but I'm not sure if that's right, especially considering it would make knowing the mass of the ball completely useless. =/
 
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The Fishman

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I think this has to do with forces. If it is possible, could you provide the pic? I think I might have an idea.
 

Nostalgia

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Vanitas-1.jpg


Oh wait, I thought of something. If I multiply 9.8 by 7.6 and get 74.48, and then use 74.48sin35° to get the x coordinate force, divide that new force by the mass again, would that be the acceleration?
 

The Fishman

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Since you know the acceleration of the ball = acceleration of the car, I believe you can use a formula (I can't remember it, something like Fcos(theta) and I believe there's another one for sine). I guess you must be certain that no outside forces like friction interfere. A free body diagram might help to see what forces are acting on the ball. It seems too simple to me, but I'll think about it a little more. Hope this helps.
 

Nostalgia

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Hi, it's me again with another physics problem that I need help with. ^_^ lol


A car is driving at 44.7 mi/hr. First, I just did the m/s conversion and got 19.983 m/s. Okay, the coefficient of friction between the tires and the road is .13. It asks what the minimum distance is in which the car will stop.

Okay, so I wanted to calculate force of friction, so I thought of Ff = mu*Fn, but I can't calculate Fn without the mass of the car. Also, even if I had force of friction, I wouldn't really know what to do next. I know the distance formulas x = ViT + 1/2at^2 and Vf^2 = Vi^2 + 2ax, but I'm not really sure of how to apply those to actual forces, since I don't the horizontal deceleration of the car.

For example, I tried (19.983)^2 = 0 + 2ax, but again, no a. =[

So, I could try to find a, but even with a = (Vf - Vi)/t, it won't help because I don't know time either. D:

Please help. I really appreciate it, and thank you in advance.
 
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Marly

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Okay KHI, right now I am having a huge brain fart. It's not really homework related, but close enough.

So in my psychology class our final grade is something like this:
Four Exams: 80%
Two Written Assignments: 20%

That makes up our final grade. Now, something happened and I missed the first exam so that's a 0 for that. So I'm wondering, taking that into account, what's the highest grade I could possibly get? Assuming I miraculously get 100 on everything else. I really want to say 80, which I hope I'm wrong but who knows. I'm pulling an all-nighter so my brain is dead. Help me out here?

The grading scale is as follows -- 90-100 A, 80-89 B etc etc.

I know I should be able to do this. But seriously I'm brain dead.

Oh, and also I have one of thos written assignments due soon, the prompt is basically this -- interpret a current event from a media source with the application of specific psychological terms and concept from the chapters in the text. (So far we've covered -- The Biology of the Mind | Consciousness and the Two-Track Mind | Nature, Nurture, and Human Diversity | Developing Trough the Life Span | Sensation and Perception.)

So any ideas on that would be wonderful and I would greatly appreciate any ideas/help.
 
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Dogenzaka

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Can someone please tell me what exactly a "rhetorical analysis paper" is? My professor is easily the most vague person on earth, and when he gave us this assignment and tried to tell us what to do, he tried to explain rhetoric by using words like rhetoric. Do I just analyze the logical, ethical and emotional tools the author uses to speak to the audience?

I didn't get a grade I wanted on the paper so I want to know for next time.
 

stephaknee

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Okay KHI, right now I am having a huge brain fart. It's not really homework related, but close enough.

So in my psychology class our final grade is something like this:
Four Exams: 80%
Two Written Assignments: 20%

That makes up our final grade. Now, something happened and I missed the first exam so that's a 0 for that. So I'm wondering, taking that into account, what's the highest grade I could possibly get? Assuming I miraculously get 100 on everything else. I really want to say 80, which I hope I'm wrong but who knows. I'm pulling an all-nighter so my brain is dead. Help me out here?

The grading scale is as follows -- 90-100 A, 80-89 B etc etc.

I know I should be able to do this. But seriously I'm brain dead.

Oh, and also I have one of thos written assignments due soon, the prompt is basically this -- interpret a current event from a media source with the application of specific psychological terms and concept from the chapters in the text. (So far we've covered -- The Biology of the Mind | Consciousness and the Two-Track Mind | Nature, Nurture, and Human Diversity | Developing Trough the Life Span | Sensation and Perception.)

So any ideas on that would be wonderful and I would greatly appreciate any ideas/help.

Yep, the highest you can get is an 80. And the assignment is pretty easy. Pretty much any current media event can be described in psychological terms. Eg: Don't Ask Don't Tell ruling + Nature, Nurture, and Human Diversity.

And yes, Dogen, rhetoric refers to Logos, Pathos, and Ethos. Ethos isn't "ethical," however. It's more like "authority." What are the author's credentials? What makes him a credible source? Why should we, as his audience, believe what he is arguing? Logos and Pathos are, like you said, appeals to logic and emotion, respectively. An important part of analyzing rhetoric is analyzing the author's style. What makes the argument convincing? Look at syntax, diction, and other literary devices.
 

Solar

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Apparently my school offers a course on cognititive sciences, it's an introduction more than anything.

My teacher strongly recommended me for it, he said if I want then it can be arranged for me to take it.

It looks very intriguing to me but from what I've gathered it seems complicated as hell. Can anyone give me a basic rundown of what to expect if I take it?
 

stephaknee

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Apparently my school offers a course on cognititive sciences, it's an introduction more than anything.

My teacher strongly recommended me for it, he said if I want then it can be arranged for me to take it.

It looks very intriguing to me but from what I've gathered it seems complicated as hell. Can anyone give me a basic rundown of what to expect if I take it?

I'm double majoring in Neuroscience and Psychology with a focus on Cognitive Neuroscience. It's really interesting and useful. Depending on the level of the course, you'll be introduced to the visual system + other sensory systems, memory, attention, emotion, social cognition, learning, and language. You'll learn the brain mechanisms behind these processes (IE: the role of the hippocampus in long-term memory, and what happens when the hippocampus gets lesioned). You'll probably briefly learn about action potetials, synaptic transmission, etc. You'll probably go over the different ways to measure brain activity (fMRI, PET, DTI, EEG/MEG).

If you like Psychology, I really recommend it. Cognitive Neuroscience is like a "science" version of Psychology.
 

Solar

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Yes, he mentioned it was the "science" under Psychology. I never was interested in the Neurology aspect of the brain, as in the medical field. He says I'm a person who appreciates the "Why" more than the "How" so I should go for it. I'm taking three sciences (in IB mind you) and it's stressful to the point that the only other IB course I take is English. I'm not sure if I need more on my plate but he's assured me it's an introduction. It's also a very small class, I wasn't even aware of it's existence, and he's teaching it so it should be "fun".

I'll see how it goes...
 

Nostalgia

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I need help not with a problem exactly, but with a Physics idea.

A mass is moving in one direction, and a frictional force is acting against it. Now, assuming the frictional force is kinetic, and therefore, less than the applied force, then the final force will be exerted, causing the object to move in the intended direction. Now, here's my question. In regards to that friction force, will the work done by that friction force be negative? This isn't one of my questions, but it'll make my answer right if this is the case. (Basically, I can get the number because I know the distance the object traveled and I know friction force, but I'm not sure if you consider friction force to be negative, since it's exerting itself onto the object to go in the other direction.)

Edit: Nvmd, got it. lol
 
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