Question

In a PMR spectrum, three groups (
peaks are observed respectively al
1.5 ppm, 3 ppm and at 7.5 ppm. The
intensities of these peaks are 3:2:5
respectively. Most probable
assignment of these peaks could be​

Answer 1

Proton nuclear magnetic resonance (proton NMR, hydrogen-1 NMR, or 1H NMR) is the application of nuclear magnetic resonance in NMR spectroscopy with respect to hydrogen-1 nuclei within the molecules of a substance, in order to determine the structure of its molecules.[1] In samples where natural hydrogen (H) is used, practically all the hydrogen consists of the isotope 1H (hydrogen-1; i.e. having a proton for a nucleus).

Answer 2

Answer:

PMR (Proton magnetic resonance) is used to identify the structure of the compound on the basis of different type of an environment of the protons.

Explanation:

• Different type of protons have different value of chemical shift.

• For the intensities ratio of the peaks 3:2:5,

1. Three protons observed at 1.5ppm due to group -CH₃(methyl).
2. Two protons observed at 3ppm due to groups -CH₂- (sp³ carbon attached with electronegative group).
3. Five protons observedat 7.5ppm due to -C₆H₅ (Phenyl group).