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
中国的四大发明是造纸术、印刷术、指南针、火药。
- I can hardly believe my eyes. Is that you, Joy?
- Yes. It has been almost ten years we were together.