Question

Which of the following statements about zeolites is not correct?

• A. Zeolites are open structures of silica in which trivalent aluminium is substituted by a fraction of silicon atoms.
• B. Shape selectivity of zeolites depends upon porous structure of the catalyst.
• C. Zeolites are synthetic microporous aluminosilicates which do not exist naturally
• D. Zeolites are aluminosilicates having three dimensional network.

Answer 1

Answer: (C)

Zeolites are synthetic microporous aluminosilicates which do not exist naturally

• The catalytic reaction that depends upon the pore structure of the catalyst and the size of the reactant and product molecules is called shape-selective catalysis.
  
• Zeolites are good shape-selective catalysts because of their honeycomb-like structures.
• Zeolites are micro porous aluminosilicates with three dimensional network of silicates in which some silicon atoms are replaced by aluminium atoms giving $Al-O-Si$ framework.
• Zeolites are found in nature as well as synthesised for catalytic selectivity.