Question

Lattice energy of NaCl(s) is -790 KJ/mol and enthalpy of hydration is -785 KJ/mol. Calcualte enthalpy of solutuon of NaCl(s).​

Answer 1

Answer:

The lattice energy of NaCl calculated using the Madelung constant of the NaCl structure type is +788 kJ/mol. The estimated enthalpy of hydration for sodium and chloride ions is -406 and -363 kJ/mol respectively.

Answer 2

Answer :

Lattice energy of NaCl = -790kJ/mol

Enthalpy of hydration = -785kJ/mol

We have to find enthalpy of solution of NaCl$.$

★ Enthalpy of solution of a substance is the enthalpy change when one mole of it dissolves in a specified amount of solvent.

$\boxed{\bf{\blue{\Delta_{sol}H^o=\Delta_{lattice}H^o+\Delta_{hyd}H^o}}}$

➠ ∆(sol)H⁰ = ∆(lat)H⁰ + ∆(hyd)H⁰

➠ ∆(sol)H⁰ = (-790) + (-785)

➠ ∆(sol)H⁰ = -1575kJ/mol

★ Explore More :

• Enthalpy of solution at infinite dilution is the enthalpy change observed on dissolving the substance in an infinite amount of solvent when the interaction between the ions are negligible.
• Lattice enthalpy of an ionic compound is the enthalpy change which occurs when one mole of an ionic compound dissociates into its ions in gaseous state.

Cheers!