Which statement about lattice energy trend is correct?

• A. Lattice energy increases with larger ion size
• B. Lattice energy increases with higher ionic charges
• C. Lattice energy decreases with higher ionic charges and smaller ion size
• D. Lattice energy increases with higher ionic charges and decreases with smaller ion size

Answer: (D)

Lattice energy reflects how strongly the ions are held together in an ionic solid, and it follows Coulomb’s law: the attraction between ions grows with the product of their charges and with shorter distances between them. So, higher charges pull ions together more strongly, increasing the lattice energy. Likewise, smaller ions mean the ions sit closer to each other, which also increases the lattice energy. Conversely, larger ions push the ions farther apart and reduce the lattice energy. The concise takeaway is that lattice energy rises with larger ionic charges and with decreasing ion size (i.e., as ions get smaller).