题目

已知1 g氢气完全燃烧生成水蒸气时放出热量121 kJ，且氧气中1 mol O===O键完全断裂时吸收热量496 kJ，水蒸气中1 mol H—O键形成时放出热量463 kJ，则氢气中1 mol H—H键断裂时吸收热量为( ) A．920 kJ                          B．557 kJ C．436 kJ                          D．188 kJ 答案：C--I left book here just now.--Is it blue one? Jack took it to the teacher.A. a; a B. the; a C. a; the D. the; the