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
12
MCQ (Single Correct Answer)
On the basis of data given below predict which of the following gases shows least adsorption on a definite amount of charcoal?
| Gas | CO$_2$ | SO$_2$ | CH$_4$ | H$_2$ |
|---|---|---|---|---|
| Critical temp./K | 304 | 630 | 190 | 33 |
A
CO$_2$
B
SO$_2$
C
CH$_4$
D
H$_2$