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【題目】Si、SiO2廣泛用于制造晶體管、光導(dǎo)纖維等。下列有關(guān)說(shuō)法正確的是

A．附著油污的晶體管可用堿液浸泡

B．光導(dǎo)纖維遇堿會(huì)影響光信號(hào)傳輸

C．工業(yè)上用SiO2熱分解法冶煉硅

D．自然界中硅以游離態(tài)形式存在

【答案】B

【解析】硅和二氧化硅與堿液都反應(yīng)，所以堿液浸泡除去油污的同時(shí)又腐蝕了晶體，A錯(cuò)誤；二氧化硅能用于制光導(dǎo)纖維、二氧化硅能與氫氧化鈉溶液反應(yīng)，生成硅酸鈉和水，所以形成光的斷路，所以光導(dǎo)纖維遇堿會(huì)影響光信號(hào)傳輸，B正確；工業(yè)上用SiO2熱還原法冶煉硅，而不是熱分解法冶煉硅，C錯(cuò)誤；硅在自然界中以化合態(tài)形式存在，如二氧化硅、硅酸鹽等，不是以游離態(tài)形式存在，D錯(cuò)誤；答案選B。

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