Redox Reactions PYQs Set 2 (PDF)

Set 2 of 5 · Questions 31-60 of 123

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Mere Teacher · Previous Year Questions NEET Chemistry · Redox Reactions · Set 2 (Q31-60)
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31. $Given below are two statements : Statement (I) : Potassium hydrogen phthalate is a primary standard for standardisation of sodium hydroxide solution. Statement (II) : In this titration phenolphthalein can be used as indicator. In the light of the above statements, choose the most appropriate answer from the options given below:$ (1) $Both Statement I and Statement II are correct$ (2) $Statement I is correct but Statement II is incorrect$ (3) $Statement I is incorrect but Statement II is correct$ (4) $Both Statement I and Statement II are incorrect$ 32. $The oxide, which cannot act as a reducing agent is$ (1) $C O_{2}$ (2) $C l O_{2}$ (3) $N O_{2}$ (4) $S O_{2}$ 33. $Observe the following reaction xS_{8} (s) + yOH^{-} (aq) \to zS^{2 -} (aq) + 2 S_{2} O_{3}^{2 -} (aq) + 6 H_{2} O (l) x, y and z are respectively.$ (1) $1, 12, 4$ (2) $1, 12, 2$ (3) $1, 4, 12$ (4) $2, 12, 2$ 34. $In the reaction, MnO_{4 (aq)}^{-} + Br_{(aq)}^{-} ⟶ MnO_{2 (s)} + BrO_{3 (aq)}^{-}, the correct change in oxidation number of the species involved is$ (1) $Br^{+ 5} to Br^{- 1}$ (2) $Mn^{+ 7} to Mn^{+ 2}$ (3) $Mn^{+ 7} to Mn^{+ 3}$ (4) $Br^{- 1} to Br^{+ 5}$ 35. $Which of the following reactions is the metal displacement reaction? Choose the right option.$ (1) $Cr_{2} O_{3} + 2 Al \to ∆ Al_{2} O_{3} + 2 C r$ (2) $Fe + 2 HCl ⟶ FeCl_{2} + H_{2} ↑$ (3) $2 Pb (NO_{3})_{2} ⟶ 2 PbO + 4 NO_{2} + O_{2} ↑$ (4) $2 KClO_{3} \to ∆ 2 KCl + 3 O_{2}$ 36. $The number of elements among O, Cl, F, N, P, Sn, Ti, K, Sc, which show more than one non-zero oxidation state is$ (1) $2$ (2) $3$ (3) $6$ (4) $8$ 37. $For the redox reaction, x MnO_{4}^{-} + y H_{2} C_{2} O_{4} + z H^{+} \to m Mn^{2 +} + n CO_{2} + p H_{2} O The values of x, y, m and n are$ (1) $10, 2, 5, 2$ (2) $2, 5, 2, 10$ (3) $6, 4, 2, 4$ (4) $3, 5, 2, 10$ 38. $What is the oxidation state of Mn in MnO_{4}^{-} ?$ (1) $+5$ (2) $+6$ (3) $+4$ (4) $+7$ 39. $The oxidation states of three carbon atoms in carbon suboxide (C_{3} O_{2}) respectively are$ (1) $+ 2, 0, + 2$ (2) $+ 2, 0, + 4$ (3) $+ 4, + 2, + 2$ (4) $- 2, + 2, 0$ 40. $Given below are two statements: Statement I: S_{8} solid undergoes disproportionation reaction under alkaline conditions to form S^{2 -} and S_{2} O_{3}^{2 -} Statement II: ClO_{4}^{-} can undergo disproportionation reaction under acidic condition. In the light of the above statements, choose the most appropriate answer from the options given below :$ (1) $Statement I is correct but statement II is incorrect.$ (2) $Statement I is incorrect but statement II is correct$ (3) $Both statement I and statement II are incorrect$ (4) $Both statement I and statement II are correct$ 41. $The oxidation number of nitrogen atoms in NH_{4} NO_{3} are$ (1) $- 3, + 5$ (2) $+ 3, - 5$ (3) $- 3, - 3$ (4) $+ 5, + 5$ 42. $In neutral or faintly alkaline medium, MnO_{4}^{-} oxidizes I^{-} to iodate. What is the number of moles of KMnO_{4} required to completely convert 1 L of 0.5 MKI to iodate?$ (1) $0.5$ (2) $4.0$ (3) $2.0$ (4) $1.0$ 43. $Which of the following is not a disproportionation reaction?$ (1) $Cl_{2} (g) + 2 OH^{-} (aq) \to ClO^{-} (aq) + Cl^{-} (aq) + H_{2} O$ (2) $F_{2} (g) + 2 OH^{-} (aq) \to OF_{2} (g) + 2 F^{-} (aq) + H_{2} O (l)$ (3) $4 ClO_{3}^{-} (aq) \to Cl^{-} (aq) + 3 ClO_{4}^{-} (aq)$ (4) $3 ClO^{-} (aq) \to 2 Cl^{-} (aq) + ClO_{3}^{-} (aq)$ 44. $3 ClO_{(aq)}^{-} ⟶ ClO 3^{-} + 2 Cl^{-} is an example of$ (1) $oxidation reaction$ (2) $reduction reaction$ (3) $disproportionation reaction$ (4) $decomposition reaction.$ 45. $Amongs the following which is redox reaction?$ (1) $N_{2} + O_{2} 2000 K 2NO$ (2) $Formation of O_{3} from O_{2}$ (3) $Reaction between NaOH and H_{2} S O_{4}$ (4) $Reaction between AgN O_{3} and NaCl$ 46. $Which of the following is only a redox reaction but not a disproportionation reaction?$ (1) $4 H_{3} PO_{3} \to 3 H_{3} PO_{4} + PH_{3}$ (2) $2 H_{2} O_{2} \to 2 H_{2} O + O_{2}$ (3) $P_{4} + 3 NaOH + 3 H_{2} O \to 3 NaH_{2} PO_{2} + PH_{3}$ (4) $P_{4} + 8 SOCl_{2} \to 4 PCl_{3} + 2 S_{2} Cl_{2} + 4 SO_{2}$ 47. $Identify the oxidation states of Mn, when MnO_{4}^{2 -} ion undergoes disproportionation reaction under acidic medium.$ (1) $+ 2, + 7$ (2) $+ 2, + 5$ (3) $+ 4, + 4$ (4) $+ 7, + 4$ 48. $What is the oxidation number of Pt in PtCl_{6}^{2 -} ?$ (1) $+6$ (2) $+4$ (3) $-4$ (4) $-6$ 49. $What are x, y and z respectively in the following reaction? xFe^{2 +} (aq) + yH^{+} (aq) + zCr_{2} O_{7}^{2 -} (aq) \to \frac{y}{2} H_{2} O (l) + xFe^{3 +} (aq) + 2 zCr^{3 +} (aq)$ (1) $14, 1, 6$ (2) $14, 6, 1$ (3) $6, 1, 14$ (4) $6, 14, 1$ 50. $Which of the following represents disproportionation of potassium chlorate?$ (1) $2 KClO_{3} ⟶ 2 KCl + 3 O_{2}$ (2) $3 KClO_{3} ⟶ 2 KClO_{2} + KClO_{3}$ (3) $4 KClO_{3} ⟶ 3 KClO_{4} + KCl$ (4) $None of the above$ 51. $When compared to Δ G^{\circ} for the formation of Al_{2} O_{3}, the Δ G^{\circ} for the formation of Cr_{2} O_{3} is$ (1) $same$ (2) $unpredicted$ (3) $higher$ (4) $lower.$ 52. $Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R Assertion A : Permanganate titrations are not performed in presence of hydrochloric acid. Reason R : Chlorine is formed as a consequence of oxidation of hydrochloric acid. In the light of the above statements, choose the correct answer from the options given below$ (1) $Both A and R are true and R is the correct explanation of A$ (2) $Both A and R are true but R is NOT the correct explanation of A$ (3) $A is true but R is false$ (4) $A is false but R is true$ 53. $One mole of Cl_{2} (g) was passed into 2 L of cold 2 M KOH solution. After the reaction, the concentrations of Cl^{-}, ClO^{-} and OH^{-} are respectively (assume volume remains constant)$ (1) $0.5 M, 0.5 M, 1 M$ (2) $0.75 M, 0.75 M, 1 M$ (3) $0.5 M, 0.5 M, 0.5 M$ (4) $1 M, 1 M, 1 M$ 54. $The oxidation state of Fe in the brown ring complex (Fe (H_{2} O)_{5} NO^{2}] SO_{4}) is$ (1) $0$ (2) $+2$ (3) $+1$ (4) $+3$ 55. $Which of the following reactions are disproportionation reactions? (A) Cu^{+} \to Cu^{2 +} + Cu (B) 3 MnO_{4}^{2 -} + 4 H^{+} \to 2 MnO_{4}^{-} + MnO_{2} + 2 H_{2} O (C) 2 KMnO_{4} \to K_{2} MnO_{4} + MnO_{2} + O_{2} (D) 2 MnO_{4}^{-} + 3 Mn^{2 +} + 2 H_{2} O \to 5 MnO_{2} + 4 H^{+} Choose the correct answer from the options given below:$ (1) $(A), (B)$ (2) $(B), (C), (D)$ (3) $(A), (B), (C)$ (4) $(A), (D)$ 56. $Balance the following equation by choosing the correct option. x KNO_{3} + y C_{12} H_{22} O_{11} ⟶ p N_{2} + q CO_{2} + r H_{2} O + s K_{2} CO_{3} x y p q r s$ (1) $36 55 24 24 5 48$ (2) $48 5 24 36 55 24$ (3) $24 24 36 55 48 5$ (4) $24 48 36 4 5 55$ 57. $In the ionic equation, BiO_{3}^{-} + 6 H^{+} + x e^{-} \to Bi^{3 +} + 3 H_{2} O, the values of x is$ (1) $6$ (2) $2$ (3) $4$ (4) $3$ 58. $Number ofmoles of M n O_{4}^{-} required to oxidize one mole of ferrous oxalate completely in acidic medium will be$ (1) $7.5 moles$ (2) $0.2 moles$ (3) $0.6 moles$ (4) $0.4 moles.$ 59. $What is the change in oxidation number of carbon in the following reaction? CH_{4} (g) + 4 Cl_{2} (g) \to CCl_{4} (l) + 4 HCl (g)$ (1) $0 to +4$ (2) $-4 to +4$ (3) $0 to -4$ (4) $+4 to +4$ 60. $What is the oxidation number of gold in the complex (AuCl_{4})^{1 -} ?$ (1) $+4$ (2) $+3$ (3) $+2$ (4) $+1$