Click on any peak for help in interpreting this spectrum.
The peak is a singlet, area 3, indicating that it corresponds to a CH3 which is not adjacent to any hydrogens (an "isolated" methyl group). The chemical shift (d 2.2) is in the region often seen for groups adjacent to mildly electronegative groups (i.e., a benzene ring or a carbonyl (but the molecule contains no oxygen)).
The peak is a singlet, area 5, indicating that it corresponds to five isolated hydrogens. The chemical shift (d 7.2) is in the aromatic region, suggesting that the molecule contains a mono-substituted benzene ring (5 hydrogens). Recall that, although there are three distinct types of ring hydrogens in mono-substituted benzene rings, splitting is typically not observed at low resolutions, hence the apparent singlet.
C7H8
From the molecular formula, the compound has "4 degrees of unsaturation" (four double bonds or rings), suggesting the possibility of an aromatic compound (benzene has four degrees of unsaturation).
IUPAC Name: toluene (methylbenzene)
The proton NMR has two peaks; a singlet at d 7.1 (5H) and a singlet at d 2.3 (3H). The peak at d 7.1 is in the aromatic region, suggesting a mono-substituted aromatic compound; the peak at d 2.3 is in the region for a methyl group adjacent a mildly electronegative group. Although mono-substituted aromatic compounds have three types of hydrogens on the ring, coupling constants between these are generally small and the chemical shifts for all three are generally comparable, making the predicted multiplet appear as a singlet.
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Structure: 