Potassium bromide (KBr) has a density of2.75 x 103 kg/m3 and the same crystal structure as NaC1. The mass of a potassium atom is 6.49 x 10-26 kg, and the mass of a bromine atom is 1.33 x 10-25 kg.
(a) Calculate the average spacing between adjacent atoms in a KBr crystal.
(b) How does the value calculated in part (a) compare with the spacing in NaC1 (see Exercise 42.15) is the relationship between the two values qualitatively what you would expect? Explain.