Question

用下列數(shù)據(jù)求氧原子的電子親和能

Mg(s)Mg(g)     ΔH₁=141 kJ·mol^-1

Mg(g)Mg²⁺(g)   ΔH₂=2 201 kJ·mol^-1

O²O(g)      ΔH₃=247 kJ·mol^-1

Mg²⁺(g)+O^2-(g)MgO(s)     ΔH₄=-3 916 kJ·mol^-1

Mg(s)+O₂(g)MgO(s)    ΔH₅=-602 kJ·mol^-1

Answer 1

氧的電子親和能為：E=-ΔH₆=-725  kJ·mol^-1

解析:

根據(jù)題給數(shù)據(jù)設(shè)計(jì)玻恩—哈伯循環(huán)

有蓋斯定律得

ΔH₅=ΔH₁+ΔH₂+ΔH₃+ΔH₄+ΔH₆

ΔH₆=ΔH₅-ΔH₁-ΔH₂-ΔH₃-ΔH₄

=-602 kJ·mol^-1-141 kJ·mol^-1-2 201 kJ·mol^-1-247 kJ·mol^-1-3 916 kJ·mol^-1=725 kJ·mol^-1