SECTION A
1. How many atoms per unit cell are present in body centered unit cell?
2. Write the IUPAC name of
3. Which of the following is more stable complex and why?
[Co(NH3)6]3+ and [Co(en)3]3+
OR
Write the IUPAC name of [Fe(en)2Cl2]Cl
4. Is this a homo polymer or copolymer?
5. Write the logarithmic expression of Freundlich adsorption isotherm
OR
What do you understand by electro kinetic potential?
SECTION B
6. a) Define molal elevation constant (Kb)
b) Why are the molecular masses of polymers determined by osmotic pressure method?
7. Show that the half-life of a first order reaction is independent of the initial concentration of the reactants.
8. Draw the structures of following: XeO3, H2S2O8
9.
10. Explain the preparation of potassium permanganate from pyrolusite ore.
OR
Complete the following equations
a) Fe2+ + Cr2O72- + H+→
b) MnO4— + S2O3 2-+H2O→
11. Write the structures of the monomers of the following polymers:
(a)Neoprene (b) Bakelite
12. Name the reagent(s) used to convert phenol to
a) benzene
b) benzoquinone
SECTION C
13. Write chemical equations when
a) Ethyl chloride is heated with silver fluoride
b) Chlorobenzene is treated with CH3COCl in the presence of anhydrous AlCl3
c) Benzyl alcohol is treated with thionyl chloride
OR
Account for the following
i) Ethyl iodide undergoes faster SN2 than ethyl bromide
ii) p-dichlorobenzene has higher melting point than those of ortho or meta isomers
iii) Haloarenes are less reactive to nucleophiles
14. An element crystallizes in fcc with edge length 200 pm. Calculate its density if 200grams of this element contains 24x 1023 atoms. [Na=6.023x1023]
15. a) What is the composition of copper matte?
b) Describe Mond’s process of refining nickel
16. Explain what is observed when
a) An electric current is passed through a sol
b) A beam of light is passed through a sol
c) An electrolyte is added to ferric hydroxide sol
OR
Write one difference between
i) Lyophobic and lyophilic colloids
ii) Heterogenous and homogenous catalysis
iii) Macromolecular and associated colloids
17. 2g of benzoic acid dissolved in 25g of benzene shows a depression in freezing point equal to 1.62K. What is the percentage association of acid if it forms dimer in solution? [Given Kf for benzene 4.9K kg/mol, molar mass of benzoic acid=122g/mol, molar mass of benzene=78g/mol]
18. What happens when D-glucose is treated with
a) HI b) NH2OH c) Br2 water
OR
What are fibrous and globular proteins? Give an example each.
19. Give reason for the following
a) Of the d4 species, Cr2+ is strongly reducing whereas Mn3+ is strongly oxidizing
b) Cu+ ion is not stable in aqueous solutions
c) Transition metals generally form colored compounds
20. a) How will you distinguish between benzoic acid and phenol?
b) Illustrate the following with chemical equations
i) Aldol condensation
ii) Gattermann-Koch reaction
Please click on below link to download CBSE Class 12 Chemistry Sample Paper 2022 Set C
