This figure shows the interaction of a cation with surrounding water molecules. (b) Which of the following explanations accounts for the fact that the ion–solvent interaction is greater for Li⁺ than for K⁺? a. Li⁺ is of lower mass than K⁺. b. The ionization energy of Li is higher than that for K. c. Li⁺ has a smaller ionic radius than K⁺. d. Li has a lower density than K. e. Li reacts with water more slowly than K. [Section 13.1]