Hydrogen PYQs Set 3 (PDF)

Set 3 of 5 · Questions 61-90 of 140

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Mere Teacher · Previous Year Questions JEE Main Chemistry · Hydrogen · Set 3 (Q61-90)
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61. $Given below are two statementsAssertion (A): Protium and deuterium differ in their rates of reactions.Reason (R): They have different enthalpies of bond dissociation.The correct answer is$ (1) $Both (A) and (R) are correct and, (R) is the correct explanation of (A)$ (2) $Both (A) and (R) are correct but (R) is not the correct explanation of (A)$ (3) $(A) is correct but (R) is incorrect$ (4) $(A) is incorrect but (R) is correct$ 62. $The one that is NOT suitable for the removal of permanent hardness of water is :$ (1) $Calgon’s method$ (2) $Ion-exchange method$ (3) $Clark’s method$ (4) $Treatment with sodium carbonate$ 63. $Which one ofthe following pairs of substances on reaction will not evolve H_{2} gas?$ (1) $Copper and HC1 (aqueous)$ (2) $Iron and steam$ (3) $Iron and H_{2} S O_{4} (aqueous)$ (4) $Sodium and ethyl alcohol (1998)$ 64. $A 30 % solution of hydrogen peroxide is$ (1) $' 30 volume' hydrogen peroxide$ (2) $' 10 volume' hydrogen peroxide$ (3) $'50 volume' hydrogen peroxide$ (4) $'100 volume' hydrogen peroxide.$ 65. $Identify the correct statements from the following: (I) The formula of Calgon in Na_{6} (PO_{3})_{6} . (II) Exhausted permutit is regenerated by aqueous KCl solution. (III)Calcium stearate is soluble in water. (IV)In ice crystals, each oxygen is surrounded by four oxygen atoms.$ (1) $III & IV only$ (2) $I & IV only$ (3) $I & III only$ (4) $II & III only$ 66. $The freezing point of heavy water at 1 atm pressure is$ (1) $0^{\circ} C$ (2) $3.8^{\circ} C$ (3) $4.8^{\circ} C$ (4) $1^{\circ} C$ 67. $Reaction of ca!gon with hard water containing Ca^{2 +} ions produce$ (1) $(Na_{2} CaP_{6} O_{18})^{2 -}$ (2) $Ca_{2} (PO_{4})_{3}$ (3) $CaCO_{3}$ (4) $CaSO_{4}$ 68. $The equation that represents the water -gas shift reaction is$ (1) $C H_{4} (g) + H_{2} O 1270 K Ni CO (g) + 3 H_{2} (g)$ (2) $CO (g) + H_{2} O 673 K Catalyst CO_{2} (g) + H_{2} (g)$ (3) $2 C (s) + O_{2} (g) + 4 N_{2} (g) 1273 K 2 CO (g) + 4 N_{2} (g)$ (4) $C (s) + H_{2} O (g) 1270 K CO (g) + H_{2} (g)$ 69. $Identify the correct statements from the following. A. In photosynthesis reaction, water is oxidized to oxygen B. An example for interstitial hydride is MgH_{2} C. Sodium hexa metaphosphate is used in the removal of permanent hardness of water.$ (1) $A, B, C$ (2) $A & B only$ (3) $B & C only$ (4) $A & C only$ 70. $Identify the reactions in which H_{2} is liberated? (i) Zn + NaOH (aq) ⟶ (ii) HCOOH \to 373 K Conc . H 2 SO 4 (iii) CH_{4} (g) + H_{2} O (g) \to 127 oK Ni (iv) Zn + H^{+} (aq) ⟶ (v) C (s) + H_{2} O (g) \to 1270 K$ (1) $(i), (iii), (iv), (v)$ (2) $(i), (ii), (iii), (iv)$ (3) $(ii), (iii), (iv), (v)$ (4) $(i), (ii), (iii), (v)$ 71. $The following methods can not be used to remove permanent hardness of water$ (1) $Treatment with washing soda$ (2) $Ion-exchange method$ (3) $Treating with Calgon$ (4) $Adding calculated amount of lime$ 72. $The strength of 11.2 volume solution of H_{2} O_{2} is: [Given that molar mass of H = 1 g mol^{- 1} and O = 16 g mol^{- 1}]$ (1) $13.6 %$ (2) $3.4 %$ (3) $34 %$ (4) $1.7 %$ 73. $Which one of the following is not a method to remove permanent hardness of water?$ (1) $Clark's method$ (2) $Calgon method$ (3) $Ion-exchange method$ (4) $Synthetic resins method$ 74. $The temporary hardness of water is due to:$ (1) $Na_{2} SO_{4}$ (2) $NaCl$ (3) $Ca (HCO_{3})_{2}$ (4) $CaCl_{2}$ 75. $At its melting point, ice is lighter than water because$ (1) $H_{2} O molecules are more closely packed in solid state$ (2) $ice crystals have hollow hexagonal arrangement of H_{2} O molecules$ (3) $on melting ofice the H_{2} O molecules shrinks in size$ (4) $ice forms mostly heavy water on first melting. (1992)$ 76. $Which metal oxide among the following gives H_{2} O_{2} on treatment with dilute acid?$ (1) $BaO_{2}$ (2) $RbO_{2}$ (3) $MnO_{2}$ (4) $Al_{2} O_{3}$ 77. $Hydrogen gas is not liberated when the following metal added to dil. HCl$ (1) $Mg$ (2) $Sn$ (3) $Ag$ (4) $Zn$ 78. $Among the following, the correct statement is$ (1) $Tritium is radioactive and emits low energy γ - rays$ (2) $H^{+} does not exist freely$ (3) $Tritium is about one atom per 10^{8} atoms of protium$ (4) $Hydrogen is very reactive compared to halogen$ 79. $Which one of the following metals forms interstitial hydride easily?$ (1) $Cr$ (2) $Fe$ (3) $Mn$ (4) $Co$ 80. $The most effective water softening method is$ (1) $Lime - soda process$ (2) $Permutit process$ (3) $Ion-exchange process$ (4) $Boiling followed by filtration$ 81. $In which of the following reactions of H_{2} O_{2} acts as an oxidising agent (either in acidic, alkaline or neutral medium) ? (i) 2 Fe^{2 +} + H_{2} O_{2} \to (ii) 2 MnO_{4}^{-} + 6 H^{+} + 5 H_{2} O_{2} \to (iii) I_{2} + H_{2} O_{2} + 2 OH^{-} \to (iv) Mn^{2 +} + H_{2} O_{2} \to$ (1) $(ii), (iii)$ (2) $(i), (iv)$ (3) $(i), (iii)$ (4) $(ii), (iv)$ 82. $CaC_{2} + 2 D_{2} O ⟶ " P " + Ca (OD)_{2} In the above reaction product " P " is$ (1) $C_{2} H_{2}$ (2) $C_{2} H_{4}$ (3) $CD_{4}$ (4) $C_{2} D_{2}$ 83. $Which ofthe following groups of ions makes the water hard?$ (1) $Sodium and bicarbonate$ (2) $Magnesium and chloride$ (3) $Potassium and sulphate$ (4) $Ammonium and chloride (I994)$ 84. $Hydrogen has three isotopes (A), (B) and (C. If the number of neutron(s) in (A), (B) and (C) respectively, are x, y and z the sum of x, y and z is :$ (1) $1$ (2) $2$ (3) $3$ (4) $4$ 85. $The correct statements about H_{2} O_{2} are: (A) used in the treatment of effluents. (B) used as both oxidising and reducing agents. (C) the two hydroxyl groups lie in the same plane. (D) miscible with water. Choose the correct answer from the options given below:$ (1) $(A), (B), (C) and (D)$ (2) $(A), (B) and (D)only$ (3) $(B), (C) and(D) only$ (4) $(A), (C) and (D)only$ 86. $Which of the following statements are correct? (i) NaH (s) reacts violently with water to form NaOH and H_{2} (ii) An example for electron rich hydride is NH_{3} (iii) Nickel forms saline hydride$ (1) $(i), (iii)$ (2) $(ii), (iii)$ (3) $(i), (ii), (iii)$ (4) $(i), (ii)$ 87. $In context with the industrial preparation of hydrogen from water gas (CO + H_{2}), which of the following is the correct statement ?$ (1) $CO is oxidised to C O_{2} with steam in the presence of a catalyst followed by absorption of C O_{2} in alkali.$ (2) $CO and are fractionally separated using differences in their densities.$ (3) $CO is removed by absorption in aqueous C u_{2} C l_{2} solution.$ (4) $H_{2} is removed through occlusion with Pd.$ 88. $Given below are two statements. Statement I : Stannane is an example of a molecular hydride. Statement II: Stannane is a planar molecule. In the light of the above statement, choose the most appropriate answer from the options given below :$ (1) $Both Statement I and Statement II are true.$ (2) $Both Statement I and Statement II are false.$ (3) $Statement I is true but Statement II is false.$ (4) $Statement I is false but Statement II is true.$ 89. $The compounds having coordinated water are CrCl_{3} 6 H_{2} O BaCl_{2} \cdot 2 H_{2} O CuSO_{4} . 5 H_{2} O I II III,$ (1) $II, III only$ (2) $I, III only$ (3) $I, II only$ (4) $I, II, III$ 90. $The strength of 50 volume solution of hydrogen peroxide is______g/L (Nearest integer).Given;Molar mass of H_{2} O_{2} is 34 g m o l^{- 1} Molar volume of gas at STP = 22.7 L,$