Question

\[\ce{AlF3}\] is soluble in HF only in presence of KF. It is due to the formation of ______. 

Options

• \[\ce{K[AlF3H]}\]

• \[\ce{K3[AlF3H3]}\]

• \[\ce{K3[AlF6]}\]

• \[\ce{AlH3}\]

Answer 1

\[\ce{AlF3}\] is soluble in HF only in presence of KF. It is due to the formation of \[\ce{K3[AlF6]}\]\.

Explanation:

Since HF is a weak acid, it cannot produce free H+ ions that can dissolve \[\ce{AlF3}\]. KF, on the other hand, is an ionic molecule that releases F-ions while dissolving \[\ce{AlF3}\] and creating the soluble complex \[\ce{K3[AlF6]}\]. Also, the ability to expand its octet and d-orbitals cause this complex to develop.