Question

$ \text{Si}{{\text{O}}_{2}} $ is soluble in:

• A. $ {{H}_{2}}S{{O}_{4}} $
• B. $ HN{{O}_{3}} $
• C. $ HF $
• D. $ HCl $

Answer 1

Answer: (C)

$ \text{Si}{{\text{O}}_{\text{2}}}\text{.} $ is soluble in HF only. Therefore/HP cannot be stored in glass or silica bottles as it attack silicates as well as silica. $ N{{a}_{2}}Si{{O}_{3}}+6HF\xrightarrow{{}}N{{a}_{2}}Si{{F}_{6}}+3{{H}_{2}}O $ $ CaSi{{O}_{3}}+6HF\xrightarrow{{}}CaSi{{F}_{6}}+3{{H}_{2}}O $ $ Si{{O}_{2}}+4HF\xrightarrow{{}}Si{{F}_{4}}+2{{H}_{2}}O $ This action of HF on silica and silicates is used for etching glass.