题干

氮化硼(BN)是一种重要的功能陶瓷材料.
(1)在与石墨结构相似的六方氮化硼晶体中,最小环上有个  ____ B原子,N原子的杂化方式为  ____ .
(2)六方氮化硼在高温高压下,可以转化为立方氮化硼,其结构与金刚石相似,硬度与金刚石相当,B原子的杂化方式为  ____ .
(3)MgO与NaCl的晶胞同为面心立方结构.每个O2周围最近的Mg2+有  ____ 个,已知MgO晶体密度为a g•cm3224
a
N
A
表示阿伏加德罗常数,则MgO晶胞体积为  ____ cm3
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3,sp2,sp3,6,40
4
×
a
*
N
A

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