A compound shows a proton NMR peak at 240Hz downfield from tms peak in...
Proton NMR Peak Analysis
Chemical Shift (δ)
The chemical shift (δ) for a proton NMR peak is calculated by dividing the difference between the resonance frequency of the peak and the resonance frequency of the reference compound (TMS) by the operating frequency of the spectrometer and multiplying by 10^6 (ppm).
δ = (240 Hz / 60 MHz) x 10^6 = 4 ppm
Therefore, the chemical shift of the proton NMR peak is 4 ppm relative to TMS.
Peak Position (t)
The position of a proton NMR peak is determined by the chemical environment of the hydrogen atoms in the molecule. The position is expressed in ppm relative to the TMS standard, where the TMS peak is assigned the chemical shift of 0 ppm.
Therefore, the position of the proton NMR peak is at 4 ppm downfield from the TMS peak.
Explanation
The proton NMR peak at 240 Hz downfield from the TMS peak indicates that the hydrogen atoms in the compound are experiencing a strong magnetic field due to their chemical environment. This chemical environment causes the hydrogen atoms to resonate at a higher frequency than TMS. The chemical shift of 4 ppm indicates that the hydrogen atoms in the compound are experiencing an electron-withdrawing group, such as a carbonyl or nitro group, which causes the protons to resonate at a higher frequency than TMS. The position of the peak at 4 ppm downfield from TMS indicates that the chemical environment of the hydrogen atoms is shielded from the TMS reference compound. This shielding effect is due to the presence of nearby electronegative atoms or groups that reduce the effective magnetic field experienced by the hydrogen atoms.
A compound shows a proton NMR peak at 240Hz downfield from tms peak in...