Question

Question: At what approximate positions might the following compounds show

IR absorptions?

(a)

Short answer

(a) It shows a distinguished absorption due to ketone at 1735$c{m}^{-1}$.

Step-by-step solution

Step-by-step SolutionStep 1:IR absorption

In general, IR absorption is caused by the interaction between the IR electric field vector and molecular dipole transition related to the molecular vibrations. Absorption is at maximum when the electric field vector and dipole transition moment are parallel to each other.

Identify the functional group

Functional groups are groups of one or more atoms with distinctive chemical properties regardless of what is attached to them.

The atoms of the functional group are bound by covalent bonds with one another and with rest of the molecule.

The functional group in compound (a) is ketone (C=O) only.

Position at which compound show IR absorptions

(a)

It shows a distinguished absorption due to ketone at 1735$c{m}^{-1}$. The functional group in thus compound is only ketone group.