【題目】下列關(guān)于硅酸的說法正確的是( )

A．硅酸可以通過SiO2和水的化合反應(yīng)制得

B．用反應(yīng)Na2SiO3＋2HCl===H2SiO3(膠體)＋2NaCl制取硅酸是利用了可溶性酸制難溶性酸的原理

C．硅酸難溶于水，不能與NaOH溶液反應(yīng)

D．硅膠可用作袋裝食品的干燥劑

【答案】D

【解析】SiO2不溶于水也不能與水反應(yīng)生成硅酸，A項錯誤；B項中反應(yīng)是利用了強酸制弱酸的原理，B項錯誤；硅酸雖難溶于水，但可與強堿溶液反應(yīng)生成硅酸鹽，C項錯誤。答案選D。

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