12th Chemistry top 20 Repeated Two Marks

1. Calculate the number of atoms in an FCC/BCC unit cell. – 4 times
2. Distinguish between ores and minerals. – 3 times
3. Give the uses of Borax. – 3 times
4. What is the inert pair effect? – 3 times
5. Which is more stable, Fe³⁺ or Fe²⁺? Why? – 3 times
6. Explain pseudo-first order reaction with an example. – 3 times
7. State Faraday’s first law of electrolysis. – 3 times
8. What are the limitations of VB theory? – 3 times
9. Write Arrhenius equation and explain the terms involved.3 Times
10. How will you identify the borate radical? – 2 times
11. Write the Kolbe’s reaction. – 2 times
12. Write the uses of silicones. – 2 times
13. Explain the common ion effect with an example. – 2 times
14. What is Chloropicrin? How is it prepared? – 2 times
15. Why does ZnO turn yellow on heating? – 2 times
16. What is Auto-reduction? Give an example. – 2 times
17. Explain the Mond’s process of refining Nickel. – 2 times
18. Sulphuric acid is a dibasic acid. Prove it. – 2 times
19. Write the Mustard oil reaction. – 2 times
20. What are epimers? Give an example. – 2 times
21. Define solubility product. – 2 times
22. How will malachite green be prepared from benzaldehyde? – 2 times
23. How is Teflon prepared? – 2 times
24. Write the Rosenmund reduction reaction. Mention the role of BaSO₄. – 2 times
25. Explain Brownian movement. – 2 times
26. What is metal deficiency defect? Give an example. – 2 times
27. What are interstitial compounds? – 2 times
28. What is the role of limestone in the extraction of iron from its oxide Fe₂O₃? – 2 times
29. What are the factors affecting adsorption? – 2 times
30. Define Autocatalysis. – 2 times
31. Calculate the standard emf of the given cell at 25°C. – 2 times
32. What are the various steps involved in the extraction of pure metals from their ores? – 2 times
33. What is meant by Burnt Alum? – 2 times
34. Write the differences between minerals and ores. – 2 times
35. What is the ionic product of water? Give its value. – 2 times
36. What is meant by the term “Coordination number”? What is the coordination number of atoms in a BCC structure? – 2 times
37. List out the properties of interhalogen compounds. – 2 times
38. Define rate law and rate constant.
39. Calculate the number of atoms in BCC unit cell.
40. Kohlrausch law?
41. Carbylamine reactions?
42. How is nylon 66 prepared?
43. Define Centre of Mass? – 2 times

Other Important Two Marks

1. Describe the role of the following in the process mentioned:
2. Define Unit cell.
3. Demerits of V.B Theory.
4. Calculate the molar conductance of 0.01 M aqueous KCl solution at 25°C.
5. How will you prepare p-hydroxy azo benzene?
6. What is chloro picric? How will you prepare?
7. Define gram equivalent conductance.
8. Write the limitations of the Ellingham diagram?
9. Calculate the number of atoms in an FCC (Face-Centered Cubic) unit cell.
10. What happens when a colloidal sol of Fe(OH)₃ and As₂O₃ are mixed?
11. How will you prepare Malachite green from benzaldehyde?
12. Write any two uses of formic acid.
13. What is Gravity separation?
14. Explain the Chromyl Chloride test.
15. Write the equation when ter-butyl methyl ether is allowed to react with 1 mole of HI.
16. Show that in the case of a first-order reaction, the time required for 99.9% completion is nearly ten times the half-life of the reaction.
17. List out the factors that affect electrolytic conductance.
18. Why does conductivity of a solution decrease on dilution?
19. What is meant by the Tyndall effect?
20. From the following reaction, identify A and B.
21. Classify the following as linear, branched, cross-linked polymer, or copolymer:
22. a) Bakelite
23. b) Nylon
24. c) Polythene
25. d) SBR rubber (Buna-S)
26. Convert glycerol to acrolein.
27. Write the IUPAC name and ligand name for the following:
28. a) CO₄²⁻
29. b) H₂O
30. Write Schotten-Baumann reaction.
31. Write the IUPAC name of the following compounds:
32. • CH₂=CH-CH₂OH
33. • C₆H₅-O-C₂H₅
34. The rate constant of a first-order reaction is 1.54×10⁻³ s⁻¹. Find its half-life period.
35. What are the various processes to prevent corrosion?
36. Write the tests for phenol.
37. Explain Popoff’s rule.
38. Draw the structure of HNO₃ and HNO₂ (Fischer projection).
39. Explain why Cr²⁺ is strongly reducing while Mn³⁺ is strongly oxidizing.
40. Sodium metal crystallizes in a BCC structure with the edge length of the unit cell as 3.0×10⁻⁸ cm. Calculate the radius of the sodium atom.
41. Account for the acidic nature of HClO in terms of Bronsted-Lowry theory. Identify its conjugate base.
42. Identify the product(s) formed when 1-methoxy propane is heated with excess HI.
43. Write Knoevenagel reaction.
44. A solution of silver nitrate is electrolyzed for 20 minutes with a current of 2 amperes. Calculate the mass of silver deposited at the cathode.
45. Define buffer solution.
46. How does glycerol react with KHSO₄?
47. What are antibiotics? Give an example.