Q. Which of the following species has the highest lattice energy?
✅ Correct Answer: (B)
MgO
Explanation: Lattice energy increases with higher ionic charges and smaller ionic radii. MgO consists of Mg2+ and O2- (charges ±2), giving much larger lattice energy compared to salts of monovalent ions like NaCl, KBr, CsI. Therefore MgO has the highest lattice energy. KBr and CsI have larger ions and lower charges, making them much lower.
Explanation by: Sikhar Chaudhary
Lattice energy increases with higher ionic charges and smaller ionic radii. MgO consists of Mg2+ and O2- (charges ±2), giving much larger lattice energy compared to salts of monovalent ions like NaCl, KBr, CsI. Therefore MgO has the highest lattice energy. KBr and CsI have larger ions and lower charges, making them much lower.