Lattice Energy Calculator

How to Use the Calculator

1. Enter the charge of the cation (e.g., +1 for Na⁺, +2 for Ca²⁺)
2. Enter the charge of the anion (e.g., -1 for Cl⁻, -2 for O²⁻)
3. Enter the interatomic distance in Angstroms (Å)
4. Click the "Calculate" button to compute the lattice energy
5. The result will be displayed in kJ/mol

Working Principle

The lattice energy of an ionic compound is the energy released when gaseous ions combine to form one mole of the solid ionic compound. It is calculated using Coulomb's law:

U = -k * (Q₁ * Q₂) / r

Where:

• U = Lattice Energy
• k = Coulomb's constant (8.988 × 10⁹ N·m²/C²)
• Q₁ = Charge of cation
• Q₂ = Charge of anion
• r = Interatomic distance

Example Calculation

For NaCl, the charges are +1 and -1, and the interatomic distance is approximately 5.64 Å:

1. Q₁ = +1, Q₂ = -1
2. r = 5.64 Å = 5.64 × 10⁻¹⁰ m
3. U = -8.988 × 10⁹ * (1 * -1) / (5.64 × 10⁻¹⁰) ≈ 1.58 × 10⁶ kJ/mol