CBSE ADDA

  Question (1): Define the terms: Acid, alkali and salt.   Answer:   An acid is a compound, which releases hydronium ions (H 3 O + ) as the only positive ions in solution. An alkali is a compound, which releases hydroxyl ions (OH - ) as the only negative ions in solution. A salt is one of the products of neutralization between an acid and a base; water being the only other product. OR A salt gives positive ions other than H + ion and negative ions other than OH - ion in solution. Question (2): Identify the number of replaceable hydrogen ions (H + ) in the following acids: HCl, CH 3 COOH, H 2 SO 4 , H 3 PO 4 . Answer:   HCl = 1    CH 3 COOH = 1       H 2 SO 4 = 2     H 3 PO 4 = 3. Question (3): What is a neutralization reaction? Answer:   Neutralization is essentially a chemical reaction between H 3 O + ions of an acid with OH - ions of the base, to give undissociated molecules of water. Question (4): What are strong and weak acids? Give one example of each? Answer:   A stron

Paper-II Secondary Classes (set-P) 01. (4) 02. (2) 03. (1) 04. (2) 05. (2) 06. (4) 07. (2) 08. (2) 09. (1) 10. (3) 11. (2) 12. (3) 13. (1) 14. (3) 15. (1) 16. (4) 17. (2) 18. (4) 19. (2) 20. (1) 21. (3) 22. (3) 23. (1) 24. (3) 25. (4) 26. (3) 27. (3) 28. (4) 29. (1) 30. (4) 31. (2) 32. (4) 33. (1) 34. (1) 35. (3) 36. (3) 37. (1) 38. (1) 39. (4) 40. (3) 41. (2) 42. (3) 43. (3) 44. (2) 45. (4) 46. (1) 47. (3) 48. (3) 49. (3) 50. (1) 51. (2) 52. (1) 53. (4) 54. (1) 55. (2) 56. (2) 57. (1) 58. (3) 59. (4) 60. (4) 61. (4) 62. (1) 63. (2) 64. (1) 65. (2)