7
MCQ (Single Correct Answer)
Which one of the following is not applicable to the phenomenon of adsorption?
A
$\Delta H>0$
B
$\Delta \mathrm{G}<0$
C
$\Delta S<0$
D
$\Delta H<0$
8
MCQ (Single Correct Answer)
Which of the following is not a favourable condition for physical adsorption?
A
High pressure
B
Negative $\Delta H$
C
Higher critical temperature of adsorbate
D
High temperature
9
MCQ (Single Correct Answer)
Physical adsorption of a gaseous species may change to chemical adsorption with ........... .
A
decrease in temperature
B
increase in temperature
C
increase in surface area of adsorbent
D
decrease in surface area of adsorbent
10
MCQ (Single Correct Answer)
In physisorption adsorbent does not show specificity for any particular gas because ........... .
A
involved van der Waals' forces are universal
B
gases involved behave like ideal gases
C
enthalpy of adsorption is low
D
it is a reversible process
11
MCQ (Single Correct Answer)
Which of the following is an example of absorption?
A
Water on silica gel
B
Water on calcium chloride
C
Hydrogen on finely divided nickel
D
Oxygen on metal surface