What Is ?_rH° for the Following Phase Change?
LiF(s) $\quad \Delta H ^ { \circ } {}_f ( \mathrm {~kJ} / \mathrm { mol } - \mathrm { rxn } )$

What is ?_rH° for the following phase change?
LiF(s) ? LiF(l)
Substance $\quad \Delta H ^ { \circ } {}_f ( \mathrm {~kJ} / \mathrm { mol } - \mathrm { rxn } )$
$\operatorname { LiF } ( s ) \quad - 616.93$
$\operatorname { LiF } ( l ) \quad - 598.65$

A) 1215.58 kJ/mol-rxn
B) 18.28 kJ/mol-rxn
C) -1215.58 kJ/mol-rxn
D) -18.28 kJ/mol-rxn
E) 0 kJ/mol-rxn