下列有关说法正确的是

题干

下列有关说法正确的是（　　）

A：含阳离子的化合物一定有阴离子

B：晶格能由大到小：NaF＞NaCl＞NaBr＞NaI

C：含有共价键的晶体一定具有高的熔、沸点及硬度

D：空间利用率：面心立方＞六方密堆积＞体心立方

上一题下一题 0.0难度选择题更新时间:2017-12-07 11:11:16

A,B

听独白，完成信息记录表。

How far is the school from Peter's home?	It's about kilometers.
How does Peter go to school?	He goes .
How many students are there?	There are students.
Where is the park?	It's the school.
What does Peter do in the park?	He plays with his friends.