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#### Surface Chemistry Model Question Paper 1

12th Standard EM

Reg.No. :
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Chemistry

Time : 01:00:00 Hrs
Total Marks : 50
5 x 1 = 5
1. For freudlich isotherm a graph of log $\frac{x}{m}$ is plotted against log P. The slope of the line and its y – axis intercept respectively corresponds to

(a)

$\frac{1}{n}$ ,K

(b)

log$\frac{1}{n}$ ,K

(c)

$\frac{1}{n}$ ,logK

(d)

log $\frac{1}{n}$ ,log K

2. Statement :
To stop bleeding from an injury, ferric chloride can be applied. Which comment about the statement is justified?

(a)

It is not true, ferric chloride is a poison.

(b)

It is true, Fe3+ ions coagulate blood which is a negatively charged sol

(c)

It is not true; ferric chloride is ionic and gets into the blood stream.

(d)

It is true, coagulation takes place because of formation of negatively charged sol with Cl-.

3. The phenomenon observed when a beam of light is passed through a colloidal solution is

(a)

Cataphoresis

(b)

Electrophoresis

(c)

Coagulation

(d)

Tyndall effect

4. According to Freundlich adsorption isotherm,

(a)

$\frac { x }{ m } =kp$

(b)

$\frac { m }{ x } ={ (kp) }^{ \frac { 1 }{ n } }$

(c)

$\frac { x }{ m } ={ kp }^{ \frac { 1 }{ n } }$

(d)

$\\ \\ \frac { x }{ m } =\frac { k }{ { p }^{ \frac { 1 }{ n } } }$

5. Pick the odd one out.

(a)

dialysis

(b)

electro dialysis

(c)

electrophoresis

(d)

ultrafiltration

6. 5 x 2 = 10
7. In case of chemisorption, why adsorption first increases and then decreases with temperature?

8. Thermal decomposition of KClO in presence of MnO2 proceeds as follows.
Steps in the reaction 2KClO → 2KCl+3Ocan be given as

9. Formation of water due to the reaction of H2 and O2 in the presence of Cu can be given as

10. Why are colloids purified?

11. Write a note on dialysis.

12. 5 x 3 = 15
13. What is the difference between a sol and a gel?

14. What do you mean by activity and selectivity of catalyst?

15. Describe some feature of catalysis by Zeolites.

16. How are colloidal solution of ink and graphite prepared?

18. 4 x 5 = 20
19. Explain intermediate compound formation theory of catalysis with an example

20. What is the difference between homogenous and hetrogenous catalysis?

21. Write the characteristics of catalysts.

22. Give the special characteristics of enzyme catalysed reactions.