One way to estimate the effective charge (Zeff) of a many-electron atom is to use the equation I1 = (1312 kJ/mol) (Z2eff/n2), where I1 is the first ionization energy and n is the principal quantum number of the shell in which the electron resides. Use this equation to calculate the effective charges of Li, Na, and K. Also calculate Zeff/n for each metal. Comment on your results.