[题目]Si.SiO2广泛用于制造晶体管.光导纤维等.下列有关说法正确的是A．附着油污的晶体管可用碱液浸泡B．光导纤维遇碱会影响光信号传输C．工业上用SiO2热分解法冶炼硅D．自然界中硅以游离态形式存在题目和参考答案——青夏教育精英家教网—

【题目】Si、SiO2广泛用于制造晶体管、光导纤维等。下列有关说法正确的是

A．附着油污的晶体管可用碱液浸泡

B．光导纤维遇碱会影响光信号传输

C．工业上用SiO2热分解法冶炼硅

D．自然界中硅以游离态形式存在

【答案】B

【解析】硅和二氧化硅与碱液都反应，所以碱液浸泡除去油污的同时又腐蚀了晶体，A错误；二氧化硅能用于制光导纤维、二氧化硅能与氢氧化钠溶液反应，生成硅酸钠和水，所以形成光的断路，所以光导纤维遇碱会影响光信号传输，B正确；工业上用SiO2热还原法冶炼硅，而不是热分解法冶炼硅，C错误；硅在自然界中以化合态形式存在，如二氧化硅、硅酸盐等，不是以游离态形式存在，D错误；答案选B。

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