Answer:
[tex]\Delta H_{298}^{0}[/tex] for the process is -375 kJ
Explanation:
[tex]P(s)+\frac{3}{2}Cl_{2}(g)\rightarrow PCl_{3}(g)[/tex]......[tex]\Delta H_{1}=-287kJ[/tex]
[tex]PCl_{3}(g)+Cl_{2}(g)\rightarrow PCl_{5}(g)[/tex]......[tex]\Delta H_{2}=-88kJ[/tex]
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[tex]P(s)+\frac{5}{2}Cl_{2}(g)\rightarrow PCl_{5}(g)[/tex]
[tex]\Delta H_{298}^{0}[/tex] = [tex]\Delta H_{1}+\Delta H_{2}=-287kJ-88kJ=-375kJ[/tex]