题目

灰锡(以粉末状存在)和白锡是锡的两种同素异形体。已知： ①Sn(s，白)＋2HCl(aq)===SnCl2(aq)＋H2(g) ΔH1 ②Sn(s，灰)＋2HCl(aq)===SnCl2(aq)＋H2(g) ΔH2 ③Sn(s，灰)       Sn(s，白) ΔH3＝＋2.1 kJ·mol－1 下列说法正确的是( ) A．ΔH1>ΔH2                                            B．锡在常温下以灰锡状态存在 C．灰锡转化为白锡的反应是放热反应 D．锡制器皿长期处在低于13.2 ℃的环境中，会自行毁坏It was reported that nine Chinese people  ______ in a balloon crash (坠毁）    in Egypt on February 26,2013.   [     ]A. are killed B. were killed.  C.  will kill. D. have killed.