Class – XII
Subject – Chemistry (Theory)
Time allowed: 3 hrs M.Marks: 70
1. Name two antidepressants.1
2. Define 12-16 compounds.1
3. . Define the pseudomolecular reactions. 1
4. Give one example of sulphonation reaction.1
5. Write IUPAC name of CH3-CH=CH-CH2- CHO1
6. Draw the structure of zwitter ion.1
7. Convert Benzene to flurobenzene.1
8. What are biodegradable polymers? Give one example.1
9. What are Antifertility drugs? Give examples.2
10. Define colligative properties with example.
2 11. A 1st order reaction is 50% complete in 30 minutes at 270C and in 10 min. at 470C.Calculate (i) rate constant for reaction at 270C and 470C.
(ii) energy of activation for the reaction.
12. What is activation energy? How is it related to rate constant K?2
13. Give four differences between types of emulsions.2
14. What are lyophobic colloids? Give two examples. How does lyophobic colloid differ from lyphillic colloids. 2
15. Compare the stability of +2 oxidation state of elements with outer electronic configuration 3d64s2,3d54s2 and 3d34s2 in aqueous solution.2 OR What is Lanthanoid Contraction? Mention two consequences of Lanthanoid contraction. 2
16. Explain the mechanism of dehydration of alcohols.2 17. Distinguish chemically between a) phenol and ethanol b) methanal and ethanal.2
18. Write the equation of the reaction involved in the preparation of Bakelite.2
19. Al crystallizes in a cubic close packing structure (FCC) Its metallic radius is 125 pm .Find 3 the edge length of the unit cell. How many unit cells are there in 1cm3 of Al ? How many atoms are there in 1cm3 of Al ?
20. Calculate the boiling point of 1M KCl solution. Density of solution=1.04g/cm3.3 Molar mass of KCl=74.5u Kb=0.52K Kg mole-1.Assume KCl is 90% dissociated in aqueous solution.
21. Give the structures of a) XeO3 b) H3PO4 c) PCl33
22. Account for the following:3
a) Zn,Cd, and Hg are not considered as transition elements. b) Actinoid show variety of oxidation states.
c) Transition metals forms alloys.
23. a) Write main postulates of werner,s co-ordination theory. b) Draw the geometrical isomers of [Co(NH3)3(NO2)3] OR What type of isomerism is exhibited by [Co(NH3)5Br]CO3? Write the IUPAC name of both the isomers. Give one chemical test to distinguish between these two isomers.3
24. Explain SN1 and SN2 Reactions. 3
25. Outline the principles of refining of the metals by the following methods:3 a) Mond’s process b) Liquation c) distillation.
26. Explain following:3