31.(广东省阳江市一模)我国采用长征三号甲运载火箭成功发射了 “嫦娥一号” 卫星。肼(N2H4)是火箭发动机的一种燃料,反应时N2O4为氧化剂,反应生成N2和水蒸气。已知:
N2(g)+2O2(g)===N2O4(g) △H=+8.7kJ/mol
N2H4(g)+O2(g)==N2(g)+2H2O(g) △H= -534kJ/mol
下列表示肼和N2O4反应的热化学方程式,正确的是
A.2N2H4(g) + N2O4(g)
= 3N2(g) + 4H2O(g) △H=–1076.7 kJ/mol
B.N2H4(g) + 1/2N2O4(g) =3/2N2(g)
+ 2H2O(g) △H=–542.7
kJ/mol
C.2N2H4(g) + N2O4(g) = 3N2(g)
+ 4H2O(g) △H=–542.7
kJ/mol
D.2N2H4(g) + N2O4(g) = 3N2(g)
+ 4H2O(l) △H=–1059.3
kJ/mol