已知在25℃,101kPa下,l gC8H18(辛烷)燃燒生成二氧化碳和液態水時放出48.40kJ熱量。表示上述反應的熱化學方程式正確的是
A.C8H18(1)+22.5O2(g)=8CO2(g)+9H2O(g);△H=-48.40kJ·mol-1
B.C8H18(1)+22.5O2(g)=8CO2(g)+9H2O(1);△H=-5518kJ·mol-1
C.C8H18(1)+22.5O2(g)=8CO2(g)+9H2O(1);△H=+5518kJ·mol-1
D.C8H18(1)+22.5O2(g)=8CO2(g)+9H2O(1);△H=-48.40kJ·mol-1