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1. What happens when an nuclei with a spin number of ½ is subjected to an applie

ID: 544877 • Letter: 1

Question

1. What happens when an nuclei with a spin number of ½ is subjected to an applied magnetic field? 2. Recalling that we can have spin up and spin down orientations; what does this diagram suggest about the applied field (%) and the energy separation (AE) of the nuclei? 1 2 1 2 Bo B, 0 Figure 1. https://www2.chemistry.msu.edu/facultylreusch/virttxtjml/spectrpy/nmrinmr1.htm 3. If the nuclei can experience the magnetic field can the electrons? Would the density of the electrons surrounding the nucleus affect what the nucleus feels? 4. We know that the individual signals provided in a classic H-NMR spectra are unique to each chemically-inequivalent hydrogen. Can you provide a reason?

Explanation / Answer

answer: -NMR is a technique that is used for determining the structure of molecules based on the energy required for nuclear spin flip

signals splitting  depends on the proton neighbors of the proton of interest , their postion in NMR is also result of the shielding and deshielded and relative intensity of signals will give the ratio of equivalent proton types

type of peaks and their meaning

Singlet means 0 equivalent hydrogen neighbors,1 peak appears

Doublet means 1 equivalent hydrogen neighbors, 2 peaks appears

Triplet means 2 equivalent hydrogen neighbors, 3 peaks appears

Quartet means 3 equivalent hydrogen neighbors, 4 peaks appears

Quintet (Pentet) means 4 equivalent hydrogen neighbors,5 peaks appears

Sextet menas 5 equivalent hydrogen neighbors,6 peaks appears

Septet means 6 equivalent hydrogen neighbors,7 peaks

due to this each chemically inequivalent hydrogen I)has a slightly different chemical shift II) represents slightly different spin flip energy III) represents nucleus with slightly different magnetic environment