Question

Physic Lab.
Help please. I have a bunch of wavelength of light green, yellow, red, violet. And I am supose to use these line to determine the gas inside the lamp. How's that possible?

Answer 1

m(lambda)=dsin(THETA). I measure calculated Slit seperation(d) and the angle, then calculated the wavelength.

Answer 2

m=1 green wavelength= 523.9nm
m=2 yellow wavelength=610nm
m=2 Green wavelength =525nm
m=1 red wavelength 724nnm
m=1Green wavelength 574nm
m=1 violet 489nm.

How can I tell what gas was in the discharge lamp.with the given wavelength.

Answer 3

I have been working on this all day, but to no avail.

Answer 4

Help please

Answer 5

Diffraction grating and spectral Analysis

Answer 6

Isn't there some sort of "look up table" of the spectra of various gases available to you ? From what I remember, if the OVERALL colour of the light (I guess without the spec anal) was, say, red, then it could have be HeNe, yellow was Na, and so on on the chemical FLAME TESTS.
Unf that wouldn't account for gases such as methane, cyanide nor other gases.
http://perendis.webs.com

Answer 7

I seem to remember you posted about a charge problem. It seems to have vanished ...
However ...
I get 13,559 V/m.
I think that the field is UNIFORM between the sheet surfaces, so it’s the same at 2cm as at 3cm, I THINK.

Answer 8

unfortunately no, I could not find any look up table online of the spectra of various gases, I still can not figure it out.

whats is the website you posted. perendis.webs could'nt find any helpful info there
And thank you, yes, I figured out the charge question.

Answer 9

hmmmmm. If it is assumed that each spectral line is characteristic of a different element, so that the emitter could have a number of elements in it, then presumably the first order spectrum will do.
according to a data booklet I've got by RM Tennent, K red is 766.5nm Cd orange is 643, He 587, Na 589 Hg 579, Fe green 527, Ca blue 422.7 all in nm.

So, I guess it's a question of "sorting out the mess" so to speak. In other words, which lines "can be attributed" to which elements. Red could be K red 766, O read A 759 , O red B 759. And that's where the spectrometer comes in, as you know better than I do.
The site i quoted is an attempt to provide useful help to interested people. Encyclopaedic it is not ... any ideas ?

Answer 10

Dont still get it. so am I to take the average of the wavelengths that I have. and then compare it to the table you are talking about

Answer 11

I am confused because the table gives only one wavelength of the discharge gas. where as I have wavelength of lines colors.

Answer 12

One last question please. what would be the precision for wavelengths. say I am doing error analysis. for instance violet 489+or- what

Answer 13

Thank you.

Answer 14

I picked ktypton as the gas in the discharge lamp, because there seem to be green appearing in differernt diffracting order, thats my argument. but the wavelength of the colours dont say much

Answer 15

pardon my english

Answer 16

I can't see the details of your problem, but I can sort of imagine possible ways round it. The problem with what I'm thinking is that it would need quite a lot of discussion, and I don't know how "important" this q is to you. Yes, it's important in its own right, but how much "background research" to be done ? That seems to be for you to judge and me to guess !
Putting it another way, is this a one off q, with the next question being on something different, or part of some research ?
Whatever it is, I wish I hope for the best.

Answer 17

I am writing my lab report and doing some error analysis on Diffraction grating and spectral Analysis.

Answer 18

Thank you.