The ¹H-NMR spectrum of one of the isomers of dibromobenzene, C₆H₄Br₂, appears as just a single peak. With which isomer is this pattern consistent?

Question

Quizplus · Accepted Answer

The ¹H-NMR spectrum of 1,4-dibromobenzene appears as a single peak due to the symmetry of the molecule. Both hydrogen atoms in the para positions are chemically equivalent and therefore give rise to the same signal in the NMR spectrum. This is not the case for 1,2- and 1,3-dibromobenzene, which have non-equivalent hydrogen atoms in different chemical environments and would therefore show multiple peaks in the NMR spectrum.

The 1H-NMR Spectrum of One of the Isomers of Dibromobenzene

The ¹H-NMR Spectrum of One of the Isomers of Dibromobenzene