• facebook
  • whatsapp
  • telegram

Surface Chemistry

1. The correct order of coagulating power of Na+, Al+3, Ba+2 ions for arsenic sulphide sol is...
Ans: Na+ < Ba+2 < Al+3
Hint:
Charge on cation - Coagulating power

 

2. The flocculation values of KCl, MgCl2, CrCl3 and SnCl4 for a −vely charged sol are in the order...
Ans: SnCl4 < CrCl3 < MgCl2 < KCl
Hint:

3. Curd is a/ an
  1) Emulsion      2) Sol      3) Gel      4) Foam
Hint:
Liquid is dispersed in solid in curd, so it is gel.

 

4. The colloidal sol used in treating eye diseases is...
Ans: Colloidal Antimony
Hint:
Argyrol is a silver sol.

 

5. The correct order of protective power of Gelatin (A), Haemoglobin (B), Gum arabic (C) and Potato Starch (D) is
Ans: A > B > C > D
Hint:

Gold Number of gelatin (0.005 to 0.01), haemoglobin (0.03), gum arabic (0.15 to 0.25), potato starch (25). 
 

6. In Freundlich adsorption isotherm, the value of  is...
Ans: 0 to 1 in all cases
Hint:
 = K.P1/n at low pressure  = 0 at high pressure  = 1 
 values = 0 to 1

 

7. Shape - Selective Catalysis is a reaction, Catalysed by
     1) Enzyme      2) Protein      3) Zeolite      4) Zeigler - Natta Catalyst
Ans: 3 (Zeolite)
Hint:
Zeolites are shape selective catalysts.

 

8. At the critical micelle concentration, the surfactant molecules
Ans: associate
Hint:
100 or more molecules associate to form micelle.

 

9. Tyndall Effect is not observed in...
    1) Smoke     2) Gold Sol     3) Emulsion     4) Brine Solution
Ans: 4 (Brine Solution) 
Hint:
Tyndall effect is not shown by true solution like brine (due to small particle size of dispersed phase).

 

10. CMC value for soaps is
Ans: 10−4 to 10−3 mol lit−1
Hint:
Critical Micelle concentration for soap is 10−4 to 10−3 mol lit−1

 

11. The basic principle of Cottrell Smoke precipitator
Ans: Neutralization of charge on colloidal particles
Hint:
Neutralization of charge present on colloidal particles.

 

12. An example of −vely charged sol is
Ans: Gelatin
Hint:
Gelatin is -vely charged sol.

 

13. The role of Fe(OH)3 in the Contact process is
Ans: to remove arsenic impurity
Hint:
Gelatinous hydrated Fe(OH)3 removes Arsenic impurities.

 

14. O/W type emulsions & W/O type emulsions are stabilized by
       1) Casein        2) Silica        3) Graphite        4) Soap
Ans: 3 (Graphite)
Hint:
Graphite powder stabilize both types of emulsions.

 

15. Incorrect enzymatic reaction among the following reactions is

Hint:
Diastase enzyme is used to convert starch into maltose.

 

16. The use of Catalyst TiCl4 + Al (C2H5)3 is
Ans: to prepare high density polyethene
Hint:
Zeigler-Natta catalyst is used to prepare H.D.P.

 

17. Incorrect match among the following is...
     1) gel liquid dispersed in solid          2) aerosol - liquid dispersed in gas 
     3) foam - gas dispersed in liquid      4) Solid Sol - Solid dispersed in liquid
Ans: 4 (Solid Sol - Solid dispersed in liquid)
Hint:
Solid dispersed in liquid is called "Sol".

 

18. A straight line for Freundlich adsorption isotherm is obtained by plotting a graph between
Ans: log  & log P
Hint:

 

19. The cleaning action of soap is due to...
Ans: due to formation of micelle & emulsion
Hint:
Initially micelle is formed An emulsion is formed between water and dirt (dissolved by non polar part)

 

20. Styptic action of alum is due to..
Ans: Coagulation of −vely charged blood by Fe+3 or Al+3 ions
Hint:
Coagulation of -vely charged blood colloid by Fe+3 or Al+3 ion

 

21. Alcohols are directly converted into gasoline by passing over heated catalyst
Ans: ZSM−5
Hint:
Hot ZSM-5 converts alcohol to gasoline

 

22. Poison for palladized charcoal in Lindlar's catalyst is
Ans: BaSO4 & Quinoline
Hint:
BaSO4 & Quinoline

 

23. Adsorption of gases on solid surface is generally exothermic because ...
Ans: "S" decreases
Hint:
Entropy (S) decreases.

 

24. The order of capability to get adsorbed by H2, CH4, SO2 is ...
Ans: SO2 > CH4 > H2

Posted Date : 15-10-2020

study-material

Previous Papers

 
 

Model Papers

 

లేటెస్ట్ నోటిఫికేష‌న్స్‌