Lattice energy increases with charge multiplicity and relative size of ions involved. For those listed, CaO has 2+/- ions and will therefore have the highest lattice energy. LiI, LiF, and RbI all have 1+/- ions. The combination of ions that have the smallest separation (assuming the ions touch, we just add ionic radii for this) will have the highest lattice energy in this group.....this would be LiF; the combination of ions that have the largest separation will have the smallest lattice energy ..... this would be RbI. Least negative ...........---> most negative RbI, LiI, LiF, CaO Ions that exist in ionic solids are surrounded by oppositely charged ions in an orderly way. Metallic ions by themselves would have have such order to them. Atoms are held together in different types of solids by different types of bonding forces. For example a network solid like diamond involves localized covalent bonds between the C atoms where as an ionic solid such as NaClinvolves the attraction of oppositely charged ions , or Coulombic forces of attraction. (This answer is not meant to be exhaustive my any means.) Solution Lattice energy increases with charge multiplicity and relative size of ions involved. For those listed, CaO has 2+/- ions and will therefore have the highest lattice energy. LiI, LiF, and RbI all have 1+/- ions. The combination of ions that have the smallest separation (assuming the ions touch, we just add ionic radii for this) will have the highest lattice energy in this group.....this would be LiF; the combination of ions that have the largest separation will have the smallest lattice energy ..... this would be RbI. Least negative ...........---> most negative RbI, LiI, LiF, CaO Ions that exist in ionic solids are surrounded by oppositely charged ions in an orderly way. Metallic ions by themselves would have have such order to them. Atoms are held together in different types of solids by different types of bonding forces. For example a network solid like diamond involves localized covalent bonds between the C atoms where as an ionic solid such as NaClinvolves the attraction of oppositely charged ions , or Coulombic forces of attraction. (This answer is not meant to be exhaustive my any means.).

1. Lattice energy increases with charge multiplicity and relative size of ions involved.
For those listed, CaO has 2+/- ions and will therefore have the highest lattice energy. LiI, LiF,
and RbI all have 1+/- ions. The combination of ions that have the smallest separation (assuming
the ions touch, we just add ionic radii for this) will have the highest lattice energy in this
group.....this would be LiF; the combination of ions that have the largest separation will have the
smallest lattice energy ..... this would be RbI. Least negative ...........---> most negative RbI, LiI,
LiF, CaO Ions that exist in ionic solids are surrounded by oppositely charged ions in an orderly
way. Metallic ions by themselves would have have such order to them. Atoms are held together
in different types of solids by different types of bonding forces. For example a network solid like
diamond involves localized covalent bonds between the C atoms where as an ionic solid such as
NaClinvolves the attraction of oppositely charged ions , or Coulombic forces of attraction. (This
answer is not meant to be exhaustive my any means.)
Solution
Lattice energy increases with charge multiplicity and relative size of ions involved.
For those listed, CaO has 2+/- ions and will therefore have the highest lattice energy. LiI, LiF,
and RbI all have 1+/- ions. The combination of ions that have the smallest separation (assuming
the ions touch, we just add ionic radii for this) will have the highest lattice energy in this
group.....this would be LiF; the combination of ions that have the largest separation will have the
smallest lattice energy ..... this would be RbI. Least negative ...........---> most negative RbI, LiI,
LiF, CaO Ions that exist in ionic solids are surrounded by oppositely charged ions in an orderly
way. Metallic ions by themselves would have have such order to them. Atoms are held together
in different types of solids by different types of bonding forces. For example a network solid like
diamond involves localized covalent bonds between the C atoms where as an ionic solid such as
NaClinvolves the attraction of oppositely charged ions , or Coulombic forces of attraction. (This
answer is not meant to be exhaustive my any means.)