Predict the relationship between the lattice energies (U) of KBr and CaO. A) U_CaO 4 U_KBr because the ionic charges are +2 and -2 and the distance between the ions is smaller. B) U_CaO 2 U_KBr because the ionic charges are +2 and -2 and the distance between the ions is smaller. D) U_CaO

Question

Predict the relationship between the lattice energies (U) of KBr and CaO. A) U_CaO > 4 U_KBr because the ionic charges are +2 and -2 and the distance between the ions is smaller. B) U_CaO < 4 U_KBr because the ionic charges are +2 and -2 and the distance between the ions is larger. C) U_CaO > 2 U_KBr because the ionic charges are +2 and -2 and the distance between the ions is smaller. D) U_CaO < 4 U_KBr because the ionic charges are +2 and -2 and the distance between the ions is larger.. E) U_CaO and U_KBrare about the same because the larger ionic charge is compensated by the larger distance between the ions.

Quizplus · Accepted Answer

The lattice energy of an ionic compound is directly proportional to the charges of the ions and inversely proportional to the distance between them. In this case, CaO has ions with charges of +2 and -2, while KBr has ions with charges of +1 and -1. The distance between the ions in CaO is also smaller than the distance between the ions in KBr. Therefore, the lattice energy of CaO is greater than the lattice energy of KBr.

Predict the Relationship Between the Lattice Energies (U) of KBr