Andhra Pradesh Board Class 12 Chemistry Sample Papers 2008

SAMPLE PAPER 2008
CHEMISTRY 
class 12

Time Allowed : 3 Hrs. Max. Marks 60

Special Instructions :-
1. You must write question paper series in the circle at top left side of title page of your
Answer-book.

2. All questions are compulsory. Internal choices have been given in some questions.

3. Question Nos. I to VI are multiple choice questions (MCQ) carry 1 (one) mark each.
Choose one correct answer among four options.

4. Question Nos VII to X are very short answer type carrying 1 (one) mark each.
Answer these questions in about one word or one line.

5. Question Nos. XI to XVII are short answer type carrying 2 (Two) marks each.
Answer these questions in about 30 words each.

6. Question Nos. XVIII to XXV are short type carrying 3 (three) marks each. Answer
these questions in about 40 words each.
7. Question Nos. XXVI to XXVIII are long type carrying 4 (four) marks each. Answer
these questions in about 50 words each.

8. Do not leave blank page / pages in your answer-book.

Q1. The coordination number of a metal crystallising in a hexagonal close packing
structure is :

(a) 12 (b) 4 (c) 8 (d) 6 1

Q2. The boiling point of solvent containing a non-volatile solute :-

(a) is decreased (b) is elevated
(c) does not change (d) None of the above 1

Q3. Galvanised iron sheets are coated with :

(a) C (b) Cu (c) Zn (d) Ni 1

Q4. The rate constant of a reaction is 1.2×10 –5 mol –2 litre² S –1 . The order of a reaction is :
(a) Zero (b) 1 (c) 2 (d) 3 1

Q5. Which type of property is the Brownian movement of colloidal sol ?

(a) Electrical (b) Optical  (c)  Mechanical (d) Colligative 1

Q6. Cinnabar is an ore of :-

(a) Hg (b) Zn (c) Ag (d) Cu 1

Q7. Define inert pair effect. 1

Q8. What is the shape of chromate ion ? 1

Q9. Write the IUPAC name of iso - butyl alcohol. 1

Q10. What happen when chloroform is exposed to air and sun light ? 1

Q11. Write the four differences between Schottky defects and Frenkel defects. 2

Q12. How many coulombs are required to deposit 50 gm of aluminium when the electrode
reaction is : Al 3+ + 3e t Al(S) 2

Q13. Write the mechanism of rusting of iron. 2

Q14. Describe the following terms :

(i) Electrodialysis (ii) Emulsion 2

Q15. (a) Give two examples of interhalogen compounds.
(b) Oxygen exist as gas while sulphur exist as a solid at room temperature. Why?
1+1=2

Q16. (a) Name the phenomenon responsible for the similar properties of Zr and Hf.
Define it.
(b) Why is the separation of lanthanoids difficult ? 1+1=2

Q17. How is potassium dichromate prepared from chromite ? 2

Q18.(a) Define coordination entity. 1

(b) How many geometrical isomers of
[Cr (en) 2 Cl 2 ]+
exist ? Which of these show optical activity ? 2

Q19. (a) Why chlorobenzene is less reactive than chloroethane ? Explain. 2

(b) How can you convert methyl chloride to ethyl chloride ? 1

Q20. Write a note on the following :

(a) Keimer - Tiemann Reaction
(b) Coupling Reaction
(c) Williamson's Synthesis   1+1+1=3

Q21. (a) Define ppm. 1

(b) A solution of glucose in water is labelled as 10% (w/w). The density of the
solution is 1.20 gm L–1 Calculate molality of solution. 2

OR

(a) Define Van't Hoff Factor 1

(b) A solution containing 12.5 gm of a non-electrolyte substance in 175 gm of
water gave boiling point elevation of 0.70 K. Calculate the molar mass of the
substance.
(K6 for water = 0.52 K Kg mol –1 ) 2

Q22. (a) Define activation energy. 1

(b) A first order reaction is 20% complete in 10 minutes. Calculate the
time for 75% completion of reaction. 2

Q23. Explain the following :

(a) PbQ2
is more stable than PbCl4

Q24. (a) How can you distinguish between :
aldehydes and ketones 1
(b) Write a note on the following :-

(i) H.V.Z. - Reaction
(ii) Cannizzaco's Reaction 2

Q25. (a) What type of bonds hold a DNA double helix together ? 1

(b) What are proteins ? State their biological importance. 2

Q26. (a) Give chemical reaction for Gabriel's phthalimide synthesis. 1

(b) Explain, why ethyl amine is more basic than aniline. 2
(c) How will you convert aniline to phenol. 1

OR

(a) Give chemical reaction for diazotization reaction and Hoffmann Bromide
reaction.

(b) What happen when :
(i) Methyl isocyanide is treated with ozone.
(ii) Methyl amine is treated wth sodium nitrite and cold dil. HCl solution.
     
Q27. (a) Write the monomers of Terylene. 1

(b) Give the preparation of :

(i) Buna - S
(ii) Orlon 2

(c) Define the Double Base Propellants. 1


Q28. (a) Define Vat Dyes

(b) Write a note on Zone refining.

(c) Complete the following reaction :-

(i) CH3 COCH3 + 4HI t ? + ? + ?
(ii) (CH3) 2 CHOH + Cu t ? + ? 2 573 K Red P423 K