Statements : Zeolites are water softener as well as catlyst .
Explanations : The catalytic atction of zeolites is based uupon their shape seclectity .
Statements : Zeolites are water softener as well as catlyst .
Explanations : The catalytic atction of zeolites is based uupon their shape seclectity .
Explanations : The catalytic atction of zeolites is based uupon their shape seclectity .
A
S is correct but E is wrong .
B
S is worong but E is correct
C
Both S and E are correct and E is correct explanation of (S) .
D
Both S and E are correct but E is not correct explanation of S.
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Zeolites is the name given to some aluminesllicates of metals with the genral formula [M_(x//n )(AlO_(2))_(x)(SiO_(2))_(3)] zH_(2)O , where n is the charge on the metal cation while z is the number of molecules of water hydration present. The metal cations participating in the zeolite formation are usually Na^(+),K^(+) or Ca^(2+) . the zeolites in the hydrated form are used as ion-exchanges in removing hardness of water. However. if these are heated in vacuum for sometime, they low the molecules of water and get dehydrated . pores or cavities are formed at the places wehre H_(2)O molecules were present. Thus, they become highly porous and can act as catalysis in certain reactions. (i) Why are zeolites called shape-selective catalysis? (ii) What is the value associated with zeolites?
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In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as (a) If both assertion and reason are true and reason is the correct explanation of assertion. (b) If both assertion and reason are true but reason is not the correct explanation of assertion. (c ) If assertion is true but reason is false. (d) If assertion and reason are false. Q. A needle placed carefully on the surface of water may float, whereas a ball of the same material will always sink. Reason: The buoyancy of an object depends both on the material and shape of the object.
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