本题目来源于试卷: Models of Bonding & Structure B.2 The Covalent Model，类别为 IB化学
[单选题]
Which of the following statements regarding silicon dioxide, $SiO_2$, are correct?
I.The structure is described as a giant covalent structure with a tetrahedral arrangement
II.The structure is insoluble in water and has a high melting point
III.The structure has a pair of nonbonding electrons present on the silicon atoms
A. I, and II only
B. I and III only
C. II and III only
D. I only
参考答案: A
本题详细解析:
$SiO_2$ has a giant covalent structure where each Si atom is singly bonded to four oxygen atoms (while maintaining a Siratio of 1:2).As there are four electron domains around each silicon atom, the structure has a tetrahedral arrangement. $SiO_2$ is held together by strong covalent bonds requiring a large amount of energy to overcome, resulting in a high melting point.The strong bonds, together with the fact that there are no charged particles present, lead to insolubility in polar solvents such as water.
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