题目

下列说法中正确的是①质子数相同的微粒一定属于同一种元素②电子数相同的微粒不一定是同一种元素③两个原子如果核外电子排布相同，一定是同一种元素④质子数相同，电子数也相同的两种微粒，不可能是一种分子和一种离子⑤所含质子数和电子数相等的微粒一定是原子⑥同种元素的原子其质量数必相等A．①②④         B．②③④           C．③④⑥           D．①⑤⑥1．Why does the woman look pale? 　　A. She is probably sick. 　　B. She feels a bit tired of her work. 　　C. She works too hard with her new students. 2．What is the relationship between the two speakers? A. Doctor and patient.　 B. Headmaster and teacher.　 C. Teacher and student.