Prediction of First-Order Multiplets

Note that the splitting of the methyl resonance into three peaks reflects that there are two H s close to it and has nothing to do with the fact that the methyl group contains three H s itself The area of the 1 2 1 methyl triplet, however, will correspond to that of three H s. 

Quintet. Five evenly spaced peaks in the frequency spectrum caused by the splitting of a single resonance by J-coupling to four identical spin-y2 nuclei to give a multiplet with five peaks with relative intensity ratios of 1 4 6 4 1. 

Multiplicity. Into how many peaks of what relative intensities the resonance from a single NMR-active atomic site in a molecule is divided. 

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