题目

They believed (古代的) Greece and Rome were important sources of knowledge. 答案：【1】ancient下列各组粒子：①H3O＋，NH4+，Na＋；②OH－，NH2-，F－；③O2－，Na＋，Mg2＋；④CH4，NH3，H2O。具有相同质子数和电子数的正确组合是（ ）A. ①②③ B. ②③④ C. ①②④ D. ①③④