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Inductive effect refers to the process or phenomenon wherein electron clouds in a bond tends to orient themselves toward the more electronegative element involved in the bond, due to which a permanent dipole arises in a given molecule by this unequal sharing of the bonding electrons in the molecule.

Inductive effect can be used in predicting the acidity and basicity of the given compounds. For example, if we take conjugate base of the acid i.e. RCOO-, here if R is electron-withdrawing group the conjugate base is stabilized via delocalization of formal negative charge and increases the acidity of the compound.

If R is electron donating group, then the conjugate base would be destabilize because of interelectronic repulsions, hence acidity decreases and basicity increases in the compound.

a. The pKa of the glutamate side-chain greater than the pKa of the aspartate side chain because the carboxyl group of the aspartic acid side chain is a stronger acid than the carboxyl group of the glutamic acid side chain because the carboxyl group of the aspartic acid side chain is closer to electron-withdrawing protonated amino group.

b. The pKaof the arginine side chain is greater than the pKaof the lysine side chain because the protonated lysine side chain is a stronger acid than the protonated arginine side chain due to less of the tendency of the arginine side chain to lose a proton as its positive charge is delocalized over three nitrogen atoms.