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#### Full Portion Five Marks Questions

12th Standard EM

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Chemistry

Time : 02:00:00 Hrs
Total Marks : 100
20 x 5 = 100
1. Explain the principle of electrolytic refining with an example.

2. Write a note on zeolites.

3. How will you convert boric acid to boron nitride?

4. Suggest a reason why HF is a weak acid, whereas binary acids of the all other halogens are strong acids.

5. A solution of [Ni(H2O)6]2+ 2is green, whereas a solution of [Ni(CN)4]2- is colorless -Explain

6. The rate constant for a first order reaction is 1.54x 10-3 s-1. Calculate its half life time.

7. The rate constant of a reaction at 400 and 200K are 0.04 and 0.02 s-1 respectively. Calculate the value of activation energy

8. Calculate i) the hydrolysis constant, ii) degree of hydrolysis and iii) pH of 0.1M CH3COONa solution (pKa for CH3COOH is 4.74).

9. 0.1M copper sulphate solution in which copper electrode is dipped at 250C . Calculate the electrode potential of copper. [Given: E0Cu2+|Cu=0.34].

10. Comment on the statement: Colloid is not a substance but it is a state of substance.

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

12. Complete the following reactions

ii) $C_6H_5-CHCH(OH)CH(CH_3)_2 \overset{ConH_2SO_4}\longrightarrow$

13. How would you distinguish between (i) methyl alcohol and ethyl alcohol (ii) benzyl alcohol and phenol, (iii) ethyl alcohol and benzyl alcohol?

14. Compound A with molecular formula C7H6O reduces Tollen's reagent and also gives Cannizaro reaction. A on oxidation gives the compound B with molecular formula C7H6O2 Calcium salt of B on dry distillation gives the compound C with molecular formula CI3H10O. Find A, Band C. Explain the reaction

15. An organic compound (A) of molecular formula C7H6O is called as oil of bitter almonds. (A) on oxidation gives (B) of molecular formula C7H6O2 which gives brisk effervescence with NaHCO3 solution. When (A) is refluxed with aqueous alcoholic (KCN) compound (C) is formed. Identify A) Band C and write the equations.

16. A Monoobromoderivative (A) on treatment with KCN followed by acid hydrolysis and heating gives a monobasic acid (B) along with liberation of CO2 . (B) on heating with liquid ammonia followed by treating with Br2 /KOH  gives (c) which on treating with NaNO2 and HCl at low temperature followed by oxidation gives a monobasic acid (D) having molecular mass 74. Identify A to D.

17. How do primary, secondary and tertiary amines react with nitrous acid?

18. What are different types of RNA which are found in cell

19. Elucidate the structure of glucose.

20. Explain the prepareation of Bakelite and Give its use.