Explain: The carbonyl group is polar and possesses electrophilic and nucleophilic centers.

(N/A) Polar bond: In the carbonyl group,the carbon-oxygen double bond is polarized due to the higher electronegativity of oxygen $(3.5)$ compared to that of the carbon $(2.5)$ atom.
As a result,the oxygen atom tends to attract the electron cloud of the $\pi$-bond towards itself,as shown by the polarization: $C=O \leftrightarrow C^{+\delta}=O^{-\delta}$.
Carbonyl compounds have substantial dipole moments and are more polar than ethers.
$(b)$ Resonance structure: The high polarity of the carbonyl group $(C^{+\delta}=O^{-\delta})$ is explained on the basis of resonance involving a neutral structure and a dipolar structure,as shown in the figure.
$(c)$ Electrophilic (Lewis acid) and Nucleophilic (Lewis base) centers: The carbon-oxygen double bond is polarized due to the higher electronegativity of oxygen relative to carbon. Hence,the carbonyl carbon acts as an electrophilic (Lewis acid) center,and the carbonyl oxygen acts as a nucleophilic (Lewis base) center.