Problem: Rubidium iodide has a lattice energy of -617 kJ/mol, while potassium bromide has a lattice energy of -671 kJ/mol.Why is the lattice energy of potassium bromide more exothermic than the lattice energy of rubidium iodide?

šŸ¤“ Based on our data, we think this question is relevant for Professor Todd's class at VANDERBILT.

FREE Expert Solution

We are asked to explain why the lattice energy of potassium bromide is more exothermic than the lattice energy of rubidium iodide.

Lattice energy represents the union of a gaseous cation and a gaseous anion in the formation of an ionic solid.


There are two main factors that contribute to the lattice energy of an ionic solid: 

  • the charge on the ions
    • as the charge of the ions increases, the lattice energy increases
  • the radius, or size, of the ions
    • as the size of the ions increases, the lattice energy decreases
View Complete Written Solution
Problem Details

Rubidium iodide has a lattice energy of -617 kJ/mol, while potassium bromide has a lattice energy of -671 kJ/mol.

Why is the lattice energy of potassium bromide more exothermic than the lattice energy of rubidium iodide?

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Lattice Energy concept. You can view video lessons to learn Lattice Energy. Or if you need more Lattice Energy practice, you can also practice Lattice Energy practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Todd's class at VANDERBILT.