Which of the following are zeolites?
This question has multiple correct options:
A) Granite
B) Faujasite
C) Natrolite
D) Thomisite

Answer Verified Verified
Hint: Zeolites were discovered by Axel Fredrik Cronstedt; famous as a mineralogist. These are basically porous in nature; composed of aluminium silicate. It functions as the molecular sieve. So, we can identify on the basis of characteristics of zeolites.

Complete answer:
> Now, first, let us discuss the zeolites. As mentioned, zeolites are porous in nature. In other words, we can say that there are spaces, or pores in between the structure; that can accommodate large numbers of cations.
> As we know, the cations are sodium ion, potassium ion, calcium ion, and the magnesium ion. These all have a positive charge on it. Thus, the pores in the zeolites can accommodate the small size ions; the large size molecules cannot be accommodated, so we named the zeolites as molecular sieve.
> If we talk about the synthesis of zeolites, it can be natural, or synthetic.
> Now, the natural zeolites are mostly obtained from the volcanoes, or the sedimentary rocks. If we talk about the synthetic zeolites; that are synthesised from the process in which there is consumption of energy.
> Let us see the examples of natural zeolites like Clinoptilolite, and Faujasite.
> There are several examples of zeolites like Analcime, Natrolite, Stilbite, and Phillipsite. In the last we can conclude that from the given options Natrolite, and Faujasite are examples of zeolites.

Hence, the correct options are (B), and (C).

Note: In this question we must know about the main property of zeolites, that is porous in nature. Here, we have considered the examples of zeolites on the basis of their synthesis to know the answer.