8/21/2019 Surface Chemistry Std.xii 2011

1/1

Mrs.Sreeja Rajmohan

REVISION QUESTIONS ON SURFACE CHEMISTRYStd. XII

1. Why is adsorption always exothermic?2. Define Kraft temperature.

3.Define activity and selectivity of a catalyst.

4. Explain reundlich adsorption isotherm.!. What is the difference "etween physisorption and chemisorption.

#. $ive an example of %&il in water' and %water in oil emulsion'.

(. )dentify the dispersed phase and dispersion medium in *el+ mil, and smo,e. -. What is the effect of temperature on chemisorption ? . Which out of /03and &2will "e more adsor"ed more readily on the surface of charcoal

and why ?

1. Define i5 6epti7ation ii5 8eversi"le sols.11. What are emulsions ?0ow are they classified? $ive suita"le examples of each type.

12. 9 colloidal solution of 9* ) is prepared "y addin* a5 9*/&3to K) and

"5 K) to 9*/&3. What is the char*e of colloidal particles in the two test tu"es a5 and "5? $ive reasons.

13. 0ow are colloids classified in the nature of forces "etween the dispersed phase and

the dispersions medium? $ive two characteri7ation of such colloids.

14. What are shape selective catalysts ? $ive example .what is their importance?1!. 0ow are the followin* colloidal solutions prepared

a5 :ulphur "5 erric hydroxide.

1#. Define the followin* terms *ivin* an example of i5 0ydrosol ii5 9erosol. 1(. Explain how the phenomenon of adsorption finds application in the followin*

processes i5 6roduction of vacuum ii5 0etero*eneous catalysis

iii5 roth floatation process. 1-. Descri"e the followin*

a5 ;ultimolecular colloids "5