In which of the following processes does the enthalpy change (ΔH) directly represent the magnitude of the lat

Question

A) Cl2(g) + 2K(s) → 2KC (s)
B) KCl(s) → K+(aq) + Cl- (aq)
C) KCl(s) → K+(g) + Cl-(g)
D) KCl(s) → K(s) + Cl-(g)
E) KCl(s) → K(s) + Cl(g)

Answer 1

None of them. C represents negative lattice energy.
It should have been in the opposite way sine lattice energy is the energy evolved when separate gaseous ions react to form 1 mole of a solid compound under standard conditions.

Answer 2

"The lat"? "The lattice energy", presumably

Lattice energy means the energy required to separate an ionic compound into its separate component free ions. So that should answer your question for you.

Hint: when stuck, remind yourself of the definitions.

Added comment: What dlt says is correct, but since you ask for the "magnitude", it doesn't matter on this occasion.