问题
选择题
甲烷是一种高效清洁的新能源,0.25mol甲烷完全燃烧生成液态水时放出222.5kJ热量,则下列热化学方程式中正确的是 [ ]
A. CH4(g) + 2O2(g) == CO2(g) +2H2O(l) ΔH= -890 kJ·mol-1
B. 2CH4(g) + 4O2(g) == 2CO2(g) + 4H2O(l) ΔH= +890 kJ·mol-1
C. CH4(g) + 2O2(g) == CO2(g) +2H2O(l) ΔH= +890 kJ·mol-1
D. 2CH4(g) + 4O2(g) == 2CO2(g) + 4H2O(l) ΔH= -890 kJ·mol-1
答案
答案:A