Question on Mass Spec/IR/NMR to identify compound

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SUMMARY

This discussion focuses on the identification of a compound using C13 NMR, H1 NMR, IR spectroscopy, and mass spectrometry without a chemical formula. Key observations include that the H1 NMR integrates to 7 hydrogens, indicating a possible multiple of 7, while the C13 NMR suggests approximately 10 carbons. The mass spectrometry analysis highlights that the parent mass peak may not always be present, and differences between peaks can indicate functional groups. The IR spectrum shows significant peaks around 1500-1600 cm-1, which may correspond to C=C double bonds or C=O stretches.

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Homework Statement


im given c13 nmr, h1 nmr, IR spec and mass spec without any chemical formula


Homework Equations


-none


The Attempt at a Solution


- i tried to start with mass spec, trying to count the highest peak to find out the total weight but i don't think that works
- also tried to find the largest peak on the IR. there are a bunch of large peaks near the 1500-1600 and one peak at around 500 cm-1
- h1 NMR integrates to give 7 H
- aproxx 10 carbons
 
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This problem is essentially impossible to answer without more information about the spectra you've been given. Here's my best shot.
Protools said:
- i tried to start with mass spec, trying to count the highest peak to find out the total weight but i don't think that works
Depending on the method used to ionize species for the mass spec, the parent mass peak is not always present. You can look at differences between peaks to get an idea of what groups are attached to the molecule (for instance, loss of successive 14 m/z units usually corresponds to loss of successive CH2 groups in an alkyl chain, or loss of 44 and 45 m/z units generally corresponds to the loss of a carboxyl group).

Protools said:
- also tried to find the largest peak on the IR. there are a bunch of large peaks near the 1500-1600 and one peak at around 500 cm-1
Peaks in this range can be C=C double bonds, phenyl rings, or C=O stretches, among other things. The 500cm-1 peak honestly gives very little information. Low frequency modes like this are usually complicated and involve many atoms.

Protools said:
h1 NMR integrates to give 7 H
With no other information, you can only say that the HNMR integrates to a multiple of 7.

Protools said:
- aproxx 10 carbons
I'm assuming this comes from the number of peaks in the C13 spectrum.
 

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