it has been a while since ive done these so i just need a refresher. im looking for the heat of hydration of lithium chloride and sodium chloride.
compound Lattice Energy deltaH soln
LiCl -834 kj/mol -37.0 kj/mol
NaCl -769 kj/mol +3.88 kj/mol
what is delta H hydration?
dHsolution = dHsolvation - lattice energy
-37 = dHhydration -(-834)
thats right now i remember! i knew it wasn't hard but its been a while. thanks! so its just -871 for LiCl
Looks like that.
Delta H hydration refers to the heat of hydration, which is the energy change associated with the dissolving of ions in water. It represents the enthalpy change when one mole of ions from a crystal lattice combines with water molecules to form hydrated ions.
To calculate the heat of hydration (delta H hydration) for a compound, you need to consider the lattice energy and the enthalpy change of solution.
The formula to calculate delta H hydration is as follows:
delta H hydration = lattice energy + delta H soln
For lithium chloride (LiCl):
Lattice energy = -834 kJ/mol
Delta H soln = -37.0 kJ/mol
delta H hydration (LiCl) = -834 kJ/mol + (-37.0 kJ/mol)
delta H hydration (LiCl) = -871.0 kJ/mol
For sodium chloride (NaCl):
Lattice energy = -769 kJ/mol
Delta H soln = +3.88 kJ/mol
delta H hydration (NaCl) = -769 kJ/mol + 3.88 kJ/mol
delta H hydration (NaCl) = -765.12 kJ/mol
Therefore, the heat of hydration for lithium chloride (LiCl) is -871.0 kJ/mol, and for sodium chloride (NaCl) is -765.12 kJ/mol.