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If I had two unknown chemicals (in solid form) mixed together, how could I go about identifying the individual components of the mixture?

Is it possible, by UV, IR, GC, or HPLC?
The problem I have is that with:
GC= sample is destroyed &
if you don't know what compound
you have, you cannot compare
retention times & sample has to be
volatile
HPLC= same problem as GC except that
compound (s) don't have to be
volatile
IR= not sure how to identify two
unknown samples in a mixture with
IR because of the combined
fingerprint regions.
UV= I know that two compounds will mix
and the spectras will add, but I
only know how to find the
concentration of each compound, if
the identity of the two compounds
are known. If the identities of
the compounds are not known, how
can I use the spectra to
find the identity of each?

Thank you

no?

Now that you state it, I realise I have a problem with the separation part. I'm not sure how much sample I'm going to be given.

I may come across as going backwards in a sense, but how would I separate two mixtures?

Thanks,
Dr.Bob

Actually you have only one mixture; it happens to have two components. There is a more or less standard procedure for separating complete unknowns (that's where you know nothing about it) and if you know nothing about it that is where you start. You have either had such a procedure already or you will be given one soon. Or consult a standard organic qualitative analysis book to see how to do it. I doubt, at the level you are, that anyone would expect you to go through the entire procedure. I'll bet that you will be give some directions as well as some glimmer of information that will help you determione what to do. I also expect you will be given more than enough sample to allow you to run a number of tests. I know I've talked in general terms, only, but with nothing more to go on, that's about the best I can do.

To identify the individual components of a mixture of two unknown chemicals in solid form, you can employ a combination of different analytical techniques. Here's how you can approach it:

1. GC (Gas Chromatography): As you mentioned, GC requires volatile compounds, so it may not be suitable for identifying solid chemicals. If the compounds can be converted into their volatile forms (e.g., by sublimation or derivatization), you can indeed use GC.

2. HPLC (High-Performance Liquid Chromatography): This technique allows for the separation and identification of non-volatile compounds. If the two unknown chemicals are soluble in an appropriate liquid mobile phase, you can try HPLC to separate and analyze the mixture.

3. IR (Infrared Spectroscopy): While IR spectroscopy alone may not provide definitive identification of each component in a mixture, it can still give valuable information about the functional groups present in the compounds. By comparing the IR spectra of the mixture to reference spectra of known compounds, you may be able to make some educated guesses about the identities of the individual components.

4. UV (Ultraviolet-Visible Spectroscopy): UV spectroscopy can provide information about the absorption of light by compounds, allowing for analysis of their concentration. While UV-Vis alone may not be sufficient to identify unknown compounds in a mixture, it can be used in combination with other techniques, such as IR or HPLC.

To maximize the chances of identifying the individual components, you can perform a combination of these techniques. Initial screening with IR or UV spectroscopy can provide some clues about the functional groups present in the mixture. Subsequently, you can use HPLC to separate the mixture and collect fractions for further analysis using GC or other spectroscopic techniques. By comparing the results obtained to reference databases, you may be able to identify the individual components based on retention times, spectral characteristics, and other parameters.

Remember, in analytical chemistry, a combination of techniques is often more powerful than relying on a single method. Therefore, it is recommended to use multiple approaches to increase the chances of accurately identifying the unknown components of a mixture.

Not really? With both IR and UV, it is difficult to superimpose one fingerprint on another, then definitely identify each separately. Either, but mainly IR, would be helpful in determining what kinds of compounds you had in the mixture (ketones, alkenes/alkanes, etc) and that gives you a handle that could be used for separating them. Usually one has enough sample to perform HPLC or TLC or something like that and have enough left over to do sample retention times. My experience, depending upon how much sample I have and what I'm dealing with, is to try to separate the mixture, then work with pure samples. That makes UV, IR, HPLC and all of the other tools MUCH more valuable. Then one can talk about individual. fingerprints. I know I've not answered your question explicitly but I hope I've give you some direction.