Hydration Enthalpy Calculator
Calculate hydration enthalpies of ions and predict solubility of ionic compounds in water.
Select Ions
Enter as positive value
Enthalpy Cycle:
Delta H(solution) = Lattice Energy + Delta H(hydration)
Enthalpy of Solution
+18 kJ/mol
Endothermic
+Na+ Hydration
-406 kJ/mol
-Cl- Hydration
-363 kJ/mol
HTotal Hydration
-769 kJ/mol
LLattice Energy
+787 kJ/mol
Solubility Prediction
Soluble
Entropy-driven dissolution
Charge Density:
Na+:
224962.89 C/pm3
Cl-:
40260.18 C/pm3
Hydration Enthalpy Trends
Hydration enthalpy becomes more exothermic (more negative) with smaller ionic radii and higher charges due to stronger ion-dipole interactions with water molecules. This explains why small, highly charged ions have very negative hydration enthalpies.
Group 1 Cations
Li+ > Na+ > K+ > Rb+ > Cs+
Halide Anions
F- > Cl- > Br- > I-