1.
在25℃、101k Pa下,0.2mol C2H2完全燃烧生成CO2和H2O(l)时放出259.92kJ热量.表示上述反应的热化学方程式正确的是( )
A.
0.2C2H2(g)+0.5O2(g)═0.4CO2(g)+0.2H2O(g)△H=+259.92 kJ/mol
B.
0.2C2H2(g)+0.5O2(g)═0.4CO2(g)+0.2H2O(l)△H=﹣259.92 kJ/mol
C.
2C2H2(g)+5O2(g)═4CO2(g)+2H2O(l)△H=+2599.2 kJ/mol
D.
2C2H2(g)+5O2(g)═4CO2(g)+2H2O(l)△H=﹣2599.2 kJ/mol