问题
选择题
— ?
—They are bananas and apples. [ ]
A. Are these bananas and apples
B. Where are they from
C. What are these
答案
答案：C
搜题请搜索小程序“爱下问搜题”
— ?
—They are bananas and apples. [ ]
A. Are these bananas and apples
B. Where are they from
C. What are these
答案：C
人类对原子结构的认识永无止境．
（1）道尔顿认为原子是“不可再分的实心球体”，汤姆生认为原子是“嵌着葡萄干的面包”，如今这些观点均______（填“正确”或“错误”），卢瑟福进行α粒子散射实验后，认为原子是“行星模型”，即原子是由带______电荷的原子核和核外电子构成．
| 1H | |||||||
| 8O | |||||||
| 12Mg | 17Cl | ||||||
选用表中元素填空A2B2型化合物的化学式是______，带一个单位负电荷的一种阴离子______．某耐火材料是由Mg，O组成的化合物，写出其化学式______．
