已知在101KPa,298K条件下,2 mol氢气燃烧生成水蒸气放出484kJ热量,下列热化学方程式正确的是( )
A.
H 2 O(g)= H 2 (g)+ 1/2O 2 ;△H(298K) = -242kJ·mol - 1
B.
H 2 (g)+ 1/2O 2 (g)= H 2 O(l);△H(298K) = +484kJ·mol - 1
C.
H 2 (g)+ 1/2O 2 (g)= H 2 O(g);△H(298K) = -242kJ·mol - 1
D.
H 2 (g)+ 1/2O 2 (g)= H 2 O(g);△H(298K) = -484kJ