What Influences Lattice Energy? A Molecular Deep Dive

The video tutorial explains lattice energy, defined by Coulomb's law, and its inverse relationship with ionic radius. It compares the lattice energies of lithium iodide, sodium iodide, and potassium iodide, highlighting how ionic size affects lattice energy. Lithium iodide has the highest lattice energy due to its smaller ionic size, while potassium iodide has the lowest due to its larger ionic size. The tutorial also discusses the role of charge magnitude in lattice energy, using lithium fluoride and magnesium oxide as examples. Magnesium oxide, with higher charge magnitudes, has greater lattice energy compared to lithium fluoride.

What is the relationship between lattice energy and ionic radius?

• Exponentially proportional

• Directly proportional

• Inversely proportional

• Unrelated

Which compound has the highest lattice energy among lithium iodide, sodium iodide, and potassium iodide?

• Potassium iodide

• Sodium iodide

• All have the same lattice energy

• Lithium iodide

Why does lithium iodide have a greater lattice energy compared to potassium iodide?

• Lower charge magnitude

• Higher charge magnitude

• Smaller ionic size

• Larger ionic size

What is the ionic size of potassium iodide?

• 1.36 angstroms

• 2.20 angstroms

• 3.56 angstroms

• 2.95 angstroms

Why does magnesium oxide have a higher lattice energy than lithium fluoride?

• Lower charge magnitude

• Larger ionic radius

• Greater charge magnitude

• Smaller ionic radius