In table salt-sodium chloride, NaCl-the Na+and Cl^- ions are arranged in a cubic crystal structure. You can observe in this structure a cube made up of eight ions: four Na^+ and four Cl^- in alternating corners. Each Na^+ has a radius of 99 pm, each Cl^- has a radius of 181 pm, and the ions are spaced as though they were solid balls of these sizes, touching their neighbors.
Part A) For a single cube of this arrangement, what are the magnitude and direction of the electric field at one of the Na^+ ions due to the other seven ions in the cube?
Part B) What are the direction and magnitude of the vector sum of the electric forces exerted on this Na^+ ion with the other seven ions?