Question

In equation δhsoln=δh1+δh2+δh3 which of the energy terms for dissolving an ionic solid would correspond to the lattice energy?

Answer 1

In the equation for the dissolution of an ionic solid, ΔHsoln = ΔH1 + ΔH2 + ΔH3, ΔH2 represents the lattice energy, which is the energy required to disrupt the ionic lattice.

Step-by-step explanation:

When dissolving an ionic solid, in the equation ΔHsoln = ΔH1 + ΔH2 + ΔH3, the energy term ΔH2 corresponds to the lattice energy. This is the energy required to overcome the electrostatic forces holding the ions in the solid lattice together. As the question described, the process of dissolving involves overcoming intermolecular interactions within both the solvent (ΔH1) and the solid lattice of the ionic solute (ΔH2), both of which are endothermic processes. The solute-solvent interactions (ΔH3) must be strong enough to compensate for these energy requirements in order for the dissolution process to be exothermic (ΔHsoln < 0). Substances like MgO with high lattice energies, typically have higher charges on their ions, leading to greater stability, higher melting points, and decreased solubility.

Answer 2

The dissolution of a solute in a solvent to form a solution usually occur in three steps, which are delta H1, delta H2 and delta H3.
For dissolving an ionic solid, the lattice energy, which is the energy that is holding the ionic particles in place correspond to DELTA H2 and it is the energy that must be conquered. The higher the charge in the ionic solid, the higher the lattice energy. The lattice energy must be overcome in order for the solid to dissolve.