NaCl molecule is bound due to the electric force between the sodium and the chlorine ions when one electron of sodium is transferred to chlorine. Taking the separation between the ions to be 2.75 × 10–8 cm, find the force of attraction between them. State the assumptions (if any) that you have made.

Given:


Charge on Na+ ion =


Charge on Cl- ion =


Distance between the ions,


________________________________________________


Formula used:


By Coulomb’s law, the electric force is given by:



Where ϵ0 is the permittivity of free space


k is the electrostatic constant


q1 and q2 are the magnitude of charges


r is the distance of separation between the charges


__________________________________________________


We assume that the distance between the transferred electron and the sodium nucleus is the distance between the two ions.





1