22. The immobilization technique involving physical method is
A.covalent bond formation dependent
B.non-covalent bond formation dependent
C.both (a) and (b)
D.ionic bond formation dependent

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23. Which of the following is the commonly employed adsorbents?
A.Calcium carbonate
B.Alumina
C.Celluloses
D.All of these

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24.  Various techniques are available for determining the effective diffusivity of solute in gel. Thin disk method uses
A.a diffusion cell with two compartments divided by a thin gel
B.a diffusion cell with two compartments C. a diffusion cell with two compartments plus by a thin gel
C.a diffusion cell with two compartments plus by a thin gel
D.a diffusion cell with two compartments multiply by a thin gel

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25. The effectiveness factor increases with the
A.increase of diffusivity and decreased with the increase of particle size
B.increase of diffusivity and increased with the increase of particle size
C.decrease of diffusivity and decreased with the increase of particle size
D.increase of diffusivity and decrease with the decrease of particle size

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