Inductive effect-the electron cloud in a sigma bond between two unlike atoms is not uniform.it is more dense towards the more electronegative of the two atoms ie the electron pair forming sigma bond is slightly displaced towards more electronegative atom this permanent state of polarization is called as Inductive effect.
Electromeric effect- on the close approach of a reagent. The electronic system of unsaturated molecule is deformed and when the reagent is removed without allowing the reaction to take place the system revers to the original ground state of the molecule.This kind of polarizability of multiple bonds is known as electromeric effect.
The effect is temporary since the electrons reverts to the original state on removing the reagent.
Acitidy increases as electronegative atom attached to carbon is increased.