The atomic radii of a divalent cation and a monovalent anion are 0.069 nm and 0.131 nm, respectively. a (a) Calculate the force of attraction between these two ions at their equilibrium interionic separation (i.e., when the ions just touch one another). i N (b) What is the force of repulsion at this same separation distance? N The force of attraction between a divalent cation and a divalent anion is 2.11 x 10-8 N. If the ionic radius of the cation is 0.072 nm, what is the anion radius? nm