What are #"lattice"# and #"hydration energies"#?

1 Answer
Dec 17, 2016

Answer:

Well, #"lattice enthalpy is..................."#

Explanation:

Well, #"lattice enthalpy is the enthalpy associated with the "#
#"formation of one mole of an ionic solid from equiv quantites"#
#"of its constituent ions, with the reactant specified to be in the"#
#"gas phase."#

And thus, for the lattice enthalpy of #"sodium chloride"# we would interrogate the thermodynamics of the reaction:

#Na^(+)(g) + Cl^(-)(g) rarr NaCl(s) +Delta#,

where #Delta-="Lattice enthalpy."#

And while this is a hard measurement to make experimentally, there are enuff good thermodynamic data to allow the measurement by data from known experiments.

And #"hydration enthalpy"# is the #"enthalpy associated with the"#
#"formation of one mole of hydrated ions from one mole of"#
#"gaseous ions that undergo hydration to give aquated ions."#

#M^(+)(g) + "excess water"rarr M^(+)(aq) +Delta#

Again, the data are good enuff to allow recourse to tabulated measurements.