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A chemical shift can be defined as the difference in frequency at which trimethyl silane absorbs the operating frequency of the spectrometer. Chemical shift is denoted by\(\delta \). The values of chemical shift vary from 1 to 10 ppm.

The chemical shift in terms of frequency while using TMS as the reference is given as:

\({\rm{\delta = }}\frac{{{{\rm{\nu }}_{{\rm{sample}}}}{\rm{ - }}{{\rm{\nu }}_{{\rm{TMS}}}}}}{{{{\rm{\nu }}_{{\rm{TMS}}}}}}{\rm{ \times 1}}{{\rm{0}}^{\rm{6}}}\,{\rm{ppm}}\)

The value of \({\rm{\delta }}\)can change from 1 to 10 ppm.

NMR spectrum of\({\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{C}}{{\rm{H}}_{\rm{2}}}{\rm{Cl}}\)

Two kinds of protons are present in\(C{H_3}C{H_2}Cl\), and they can split each other. The\({\rm{C}}{{\rm{H}}_{\rm{3}}}\)signal will be split by\({\rm{C}}{{\rm{H}}_{\rm{2}}}\) protons into \(2 + 1 = 3\)peaks. The peak obtained will be upfield from the \({\rm{C}}{{\rm{H}}_{\rm{2}}}\)protons since the \({\rm{C}}{{\rm{H}}_{\rm{3}}}\)protons are farther from the \({\rm{Cl}}\).

Then, the \({\rm{C}}{{\rm{H}}_{\rm{2}}}\) signals will be split by the \({\rm{C}}{{\rm{H}}_{\rm{3}}}\) protons into \(3 + 1 = 4\)peaks. The peak obtained will be downfield from the \({\rm{C}}{{\rm{H}}_{\rm{3}}}\) protons since the \({\rm{C}}{{\rm{H}}_{\rm{2}}}\) protons are closer to the\({\rm{Cl}}\). The ratio of integration units will be 3:2.