题目

Almost all the houses in the city are said ________ in the terrible earthquake. A. to destroy                         B. having destroyed    C. to have been destroyed               D. to have destroyed 答案：C南京理工大学胡炳成团队用新方法制得了NaN5•3H2O．该化合物中含有N5﹣等微粒。已知N为7号元素，则下列有关说法正确的是（　　）A. NaN5•3H2O是一种氧化物B. N5﹣是一种单质C. 1个N5﹣中共含有35个质子D. 1个N5﹣中共含有34个电子