the atomic radii of a divalent cation and a monovalent anion are 0.057 nm and 0.137 nm, respectively. (a) Calculate the force of attraction between these two ions at their equilibrium interionic separation (i. e., when the ions just touch one another). N (b) What is the force of repulsion at this same separation distance? N

not too sure thinking it will always be directed towards the centre of the earth. could be wrong not sure

force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y