For times when you need HELP!!!
(You can read the 2009 edition here.)
Patience, Please
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For times when you need HELP!!!
(You can read the 2009 edition here.)
It seems like the start of the school year would be a more sensible time to start this…
Ah, I see this thought has already come up. That makes sense.
Not for those of us with summer homeworks, sadly.
Hmmm… I’m probably one of the only people who has homework on a daily to weekly basis at the moment. But somehow I don’t think that this is the place to ask for help proving strong induction through set theory or solving the Traveling Salesman Problem. (Although if you can solve the Traveling Problem, please tell me, since you would get a million dollars. The homework is just to prove that it’s NP-complete.)
If you’re taking two quotes from different pages of a book and embedding them in the same sentence, how would you cite the page number in standard MLA format?
The closest thing I can find is quoting two different sources in one sentence:
“To cite multiple sources in the same parenthetical reference, separate the citations by a semi-colon:
. . . as has been discussed elsewhere (Burke 3; Dewey 21).”
What I would do is something like this:
“. . . as has been discussed elsewhere (Burke 3; Burke 21).”
or
“. . . as has been discussed elsewhere (Burke 3, 21).”
or something along those lines.
The last one is correct, I believe. It’s (Burke 3, 21).
Could anyone tell me the equations for a right triangle
For area? A=bh.
Correction, that would be A = (bh)/2. Don’t want to be finding the area of something twice the size of that little old triangle! I love triangles.
O-h. Snap. Knew that.
What do you mean, “the equations for a right triangle”? Sine, cosine, and tangent? Or the Pythagorean theorem? Which equations?
Which equations??? I’m sorry, I’m really obsessed with math, especially all the things you can do with right triangles!
Pythagorean Theorm:
a^2 + b^2 = c^2
(With a and b being the legs of the triangle, the ones making up the 90 degree angle, and c being the hypotenuse)
Trigonometric Functions:
(Choose an angle within the right triangle…)
Sine = Opposite/Hypotenuse
Cosine = Adjacent/Hypotenuse
Tangent = Opposite/ Adjacent
(Remember these with a helpful acronym: SOH CAH TOA: Saddle Our Horses, Canter Away Happily, To Other Adventures)
Um, I don’t remember any more dealing specifically with right triangles… I was about to go listing off some trigonometric identities, then realized that they don’t really have much to do with right triangles, unless they’re inscribed within a circle with a radius of 1. But I’m really rambling. Sorry.
Woah, everyong answered at the same time!
I need tips on how to memorize what each symbol and what it stands for on the periodic table.
Reviving a dead thread because I am utterly lost
I have been trying to understand oxidation reactions/half-reactions for 2 and a half hours now. I understand them in their basics. I just don’t understand how they are suddenly being used on my pre-lab worksheet that is a lot of points.
We learned basic stuff like
@ Fe(+2) + Cl2 -> 2Fe(+3) + 2Cl(-1)
to reduction half
Cl2 + 2e(-1) -> 2Cl(-1)
and oxidation half
Fe(+2) -> Fe(+3) + e(-1)
(stuff in () is charges)
And then now my lab is asking:
“In an acidic solution, premanganate ion oxidizes species A to VO2(+1). How many moles of electrons must be transferred to MnO4(-1) by each mole of species A if Species A is a)VO(+2), b) V(+3), c) V(+2)”
what
There is nothing in either of my books or my notebook explaining this and I can’t tell anymore if it’s just too late and I can’t think right or it’s weird and stuff. Same with the questions
“If 30.00mL of .200-M MnO4(-1) reacted with species A to produce Mn(2+) and VO2(+1), how many total moles of electrons were transferred from species A to permanganate? (You should ignore species A and VO2(+1) in obtaining the answer, since you are given quantitative information about MnO4(-1) only)”
all I could get was “5e(-1) + 8H + MnO4(-1) -> Mn(+2)+ 4H20” and only with the help of the internet, and now I’m not even sure where to go form there or if it’s even right. !^$%*.
(and other questions I am not going to bother typing up because they are just for me to rant about really, I don’t expect any responses >.<)
which I just can’t seem to get my head around. I don’t know if it’s just because it’s late now (though it didn’t make any sense to me earlier either) or if I’ve hit the wall in my head that tries to block out all chemistry learning again. I had the same problem in high school–I got biology and stuff super easy, but chem just never worked out inside my head.
And it’s due tomorrow at 8 and I have class from 9:30 to 11, then from 1:30-4:30 and then practice 4:45-5:45, then team dinner, then a meeting at 7, then as soon as that finishes I have to run to another class from 7-9.
So I have to finish this by like 1 or I’m screwed. I don’t even know. I wish I had a better teacher for the lecture half of chem because I feel like I’m not really learning form him, and he also wrote the textbook we use so I can’t get a different person’s view on it, and the stuff on the prelab isn’t even covered in it. I don’t know how the hell we were supposed to understand how to do it. It doesn’t help that I don’t know anyone in the class, and none of my friends seem to be taking/good at chem either so I’m really stuck and UHG
yeah just ranting/panicking a bit, not really expecting replys but asfjkhk;gshkadj
Ack. Chemstry strikes back. I’m going to compare with my friends anyway, but it would be really swell if someone could help me…
1) What Energy does a Photon with a wavelength of 600 nm have? I’ve tried calculating it every way I know of, but I never even get close to the result that Wikipedia suggests (2,12- 1,915 eV, unless I misunderstood that too). Besides, I’m not sure which plank’sche Number I’m supposed to use.
2) Which Wavelenght corresponds with an Elektron circling a H-atom (in Bohr’s modell) at 2,10^6 m/s? ((This must have been the class I missed because I just don’t get it).
The equation you’re looking for is a variation on Plank’s equation, (E = hν) where ν, the frequency, is replaced withe the wavelength. This is calculated using c = λv, so v = c/λ. So, what you’re left with is E = hc/λ. h is Plank’s constant, 6.62606876 x 10^-34 J*s. c is the speed of light, 2.99792458 m/s.
Your answer will be in Joules becuause c is in m/s, λ is in m, and h is in J*s. Both the meters and seconds cancel out, so you’re left with Joules.
Hope I helped! Now back to math homework.
Appendix: So you will have to convert the 600 nm into m to use this. Or the speed of light into nm/s.
Yes! *victory dance* Thankyouthankyouthankyou!