问题
选择题
已知在25℃,101kPa下1g C8H18(辛烷液体)燃烧生成二氧化碳和液态水时放出48.40kJ热量。表示上述反应的热化学方程式正确的是[ ]
A.C8H18(l)+ 25/2O2(g)=8CO2(g)+9H2O(g)△H=-48.40kJ/mol
B.C8H18(l)+ 25/2O2(g)=8CO2(g)+9H2O(l)△H=-5518kJ/mol
C.C8H18(l)+ 25/2O2(g)=8CO2(g)+9H2O(g)△H=+5518kJ/mol
D.C8H18(l)+ 25/2O2(g)=8CO2(g)+9H2O(l)△H=+48.40kJ/mol
答案
答案:B