6.
下面均是正丁烷与氧气反应的热化学方程式\(\rm{(25℃,101 kPa)}\):
\(\rm{①C_{4}H_{10}(g)+13/2}\) \(\rm{O_{2}(g)=4CO_{2}(g)+5H_{2}O(l);}\) \(\rm{Δ}\)\(\rm{H}\)\(\rm{=-2 878 kJ·mol^{-1}}\)
\(\rm{②C_{4}H_{10}(g)+13/2}\) \(\rm{O_{2}(g)=4CO_{2}(g)+5H_{2}O(g);}\) \(\rm{Δ}\)\(\rm{H}\)\(\rm{=-2 658 kJ·mol^{-1}}\)
\(\rm{③C_{4}H_{10}(g)+9/2}\) \(\rm{O_{2}(g)=4CO(g)+5H_{2}O(l);}\) \(\rm{Δ}\)\(\rm{H}\)\(\rm{=-1 746 kJ·mol^{-1}}\)
\(\rm{④C_{4}H_{10}(g)+9/2}\) \(\rm{O_{2}(g)=4CO(g)+5H_{2}O(g);}\) \(\rm{Δ}\)\(\rm{H}\)\(\rm{=-1 526 kJ·mol^{-1}}\)
由此判断,正丁烷的燃烧热\(\rm{Δ}\)\(\rm{H}\)为