Silica is a network solid with Si - O - Si bonds. In many aluminosilicates, a few Si atoms in the silica structure are replaced by Al atoms. Zeolites, clays, asbestos etc. are examples of aluminosilicates having different structures. The statement which is NOT correct is:

Options

1. AThe basic structural unit in silicates is tetrahedral ( SiO ₄ )⁴⁻ .
2. BReplacement of a Si atom in silica by an Al atom results in negative charge on the Al atom.
3. CSilica dissolves in aqueous NaOH to form sodium silicate in which Na ⁺ is bonded to oxyanions.
4. DSilicones are examples of silicates.