The inductive effect can be explained with Bents rule. The inductive effect is the transmission of charge through covalent bonds and Bents rule provides a mechanism for such results via differences in hybridisation. In the table below, as the groups bonded to the central carbon become more electronegative, the central carbon becomes more electron-withdrawing as measured by the polar substituent constant. The polar substituent constants are similar in principle to &sigma; values from the Hammett equation, as an increasing value corresponds to a greater electron-withdrawing ability. Bent's rule suggests that as the electronegativity of the groups increase, more p character is diverted towards those groups, which leaves more s character in the bond between the central carbon and the R group. As s orbitals have greater electron density closer to the nucleus than p orbitals, the electron density in the C&minus;R bond will more shift towards the carbon as the s character increases. This will make the central carbon more electron-withdrawing to the R group. Thus, the electron-withdrawing ability of the substituents has been transferred to the adjacent carbon, as the inductive effect predicts.