akushuki
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Sun Oct-08-06 10:08 PM
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Chemistry repeat performance? |
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Last time I had a really hard chemistry problem. 4 weeks ago, DU bailed my ass out. Its been rather painful as I've been working on this for about 8 hours. I got all the other ones in this set except this one.:eyes: A repeat performance please?
λ for one line of the hydrogen spectrum is .4118 x 10-4 cm. Use this value in the Rydberg equation to calculate the RH value using n1 = 2, and n2 = 3.
So heres what I did. I took .4118X10-4 cm and made it into m.
So λ=.4118 X 10-6 m
then
1/λ= R(1/n1-1/n2)
1/.4118 X 10-6 = R(5/36)
1/R=.00000057/1 .00000057R=1 R=1754385.965 R=1.754X10^-6
This is apparently wrong. Any hints, tips, solutions, ect. would be greatly appreciated.:)
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sir_captain
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Sun Oct-08-06 10:21 PM
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Edited on Sun Oct-08-06 10:21 PM by sir_captain
1.748*10^7 m^-1?
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akushuki
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Sun Oct-08-06 10:23 PM
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sir_captain
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Sun Oct-08-06 10:25 PM
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well, for one thing, you forgot to square your n's in the equation you wrote
i will have to ponder this slightly longer--hope i can help
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akushuki
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Sun Oct-08-06 10:29 PM
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4. i just couldnt find the easy way to make the squares and didnt bother |
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if i wrote out the entire thing i did, it would have been 1/n1 - 1/n2 1/22 - 1/32 1/4- 1/9 9/36-4/36 5/36
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sir_captain
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Sun Oct-08-06 10:32 PM
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5. do you have the correct answer? |
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this seems to be a pretty straight-forward balmer series problem. i'm a little puzzled about the wavelength you have to start with, though.
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akushuki
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Sun Oct-08-06 10:46 PM
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7. I get chemistry hw and prelabs on this stupid thing called CAPA |
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basically, if its not in a form its happy with, it sends hate through the internet tubes.
2. <1pt> λ for one line of the hydrogen spectrum is .4118 x 10-4 cm. Use this value in the Rydberg equation to calculate the RH value using n1 = 2, and n2 = 3.
Answer: <____________> Last Answer: 1.754e7 Incorrect, tries 28/99.
1.748e7 didnt work either :(
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sir_captain
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Sun Oct-08-06 10:53 PM
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I'm reasonably certain that is the correct answer given the information you have been given.
You could try 1.75e7 and see if it only wants one decimal point or something.
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akushuki
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Sun Oct-08-06 10:57 PM
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λ for one line of the hydrogen spectrum is .4118 x 10-4 cm. Use this value in the Rydberg equation to calculate the RH value using n1 = 2, and n2 = 3.
Answer:<> Last Answer: 1.75e7 Please adjust significant figures, tries 32/99.
I'm about to fix my computer with a hammer. Everyone is saying that is my answer, but CAPA says 'NO! lolz.' :(
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sir_captain
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Sun Oct-08-06 11:00 PM
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11. The whole question is dumb |
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why would they want you to calculate a constant? This equation is normally used to calculate a wavelength, not the other way around. And 411nm is an odd wavelength for hydrogen.
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akushuki
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Sun Oct-08-06 11:08 PM
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12. I agree that it is dumb |
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However, despite the dumbness, I still need to figure it out.
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Ptah
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Sun Oct-08-06 10:39 PM
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R=1754385.965 R=1.754X10^-6
Shouldn't that be R=1.754X10^6
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akushuki
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Sun Oct-08-06 10:46 PM
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but that isnt it either. :(
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akushuki
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Sun Oct-08-06 11:24 PM
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13. I posted this on Freeperville but I got the answer |
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"Type 'God did it' "
Not really. Just bumping the thread a little with a joke.
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sir_captain
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Sun Oct-08-06 11:29 PM
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14. Sorry I can't be more help |
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do you know anyone who has gotten it right?
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akushuki
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Sun Oct-08-06 11:31 PM
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Every other person in chemistry 111 on my floor has lab on Thursday and dont do them until tuesday/wednesday. I have mine on Monday, which is in about 11 1/2 hours from now. :(
I started at 3 yesterday(sunday)
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sir_captain
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Mon Oct-09-06 12:03 AM
Response to Reply #15 |
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if it makes you feel any better, I've been memorizing the anatomy of the back and upper limb pretty much non-stop since friday night.
How much is this one question worth, relatively?
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