ECAT Chemistry Reaction Kinetics Test Online

1. For the reaction PCl₅(g) ⇌ PCl₃(g) + Cl²(g) the forward reaction at constant temperature is favoured by

2. When a reaction proceeds in a sequence of steps, the overall rate is determined by

3. A first order reaction is 75% complete after 32 minutes. When was 50% of the reaction completed?

4. The rate of chemical reaction depends on the nature of reactants because

5. 1.1 mol of A is mixed with 2.2 mol of B and the mixture is kept in one liter flask till the equilibrium is reached. At equilibrium, 0.2 mol of C is formed. If the equilibrium reaction is A + 2B 2C + D, the value of equilibrium constant is

6. Which statement about the following equilibrium is correct? 2SO₂(g) + O₂(g) → 2SO₃(g) ∆H = -188.3 kJmol¯³

7. Which of the solution among the following has highest pH?

8. If the rate of reaction for 2A + B → Products is K [A]² [B] and A is present in large excess, then order of reaction is

9. Oxidation of oxalic acid by acidified KMnO₄ is an example of autocatalysis, it is due to which of the following?

10. RCOOR + H₂O HIC→ RCOOH + R’OH. What type of reaction is this?

11. Which statement is incorrect for a buffer solution?

12. The value of Kp is greater than Kc for a gaseous reaction when

13. 1 mole of hydrogen and 2 moles of iodine are taken initially in a 2 liter vessel. The number of moles of hydrogen at equilibrium is 0.2. Then the number of moles of iodine and hydrogen iodide at equilibrium are

14. The rate of reaction

15. The experimental relationship between a reaction rate and concentration of reactants is called

16. 1 mole of N₂ and 2 moles of H₂ are allowed to react in a 1 dm³ vessel. At equilibrium 0.8 mole of NH₃ is formed. The concentration of H₂ in the vessel is

17. If initial concentration of reactants in certain reaction if doubled, the half-life period of the reaction doubles, the order of a reaction is

18. One the basis of Le-Chatelier’s principle, predict which of the following conditions would be unfavourable for the formation of SO₃? Given that 2SO₂ + O₂ ⇌ 2SO₃; ∆H = -42 kcal

19. The rate at which a substance reacts depends on its

20. If the rate of reaction for 2A + B → Products is K [A]² [B] and A is present in large excess, then order of reaction is

21. The dimension of rate constant of a second order reaction involves

22. For a reaction of type A + B → products it is observed that doubling concentration of A causes the reaction rate to be four times a great, but doubling amount of B does not affect the rate. The rate equation is

23. Factor which slows down the rate of reaction is

24. The activation energy for a reaction is 90 keal mol¯¹ the approximate increase in rate constant, when it’s temp is increased from 300K to 310K is

25. A substance ‘A’ decomposes in solution following the first order kinetics. Flask I contains 1 L of 1 M solution of A and flask II contains 100 ml of 0.6 M solution. After 8 hr the concentration of A in flask 1 become 0.25 M, what will be the time for concentration of A is flask II to become 0.3 M

26. Collision theory is application to

27. Which of the following is a characteristic of a reversible reaction?

28. For a chemical reaction ______ can never be a fraction

29. The rate of reaction

30. In a reversible reaction, two substance are in equilibrium. If the concentration of each one is reduced to half, the equilibrium constant will be

31. One mole of compound AB reacts with one mole of a compound CD according to the equation AB(g) + CD(g) ⇌ AD(g) + CB(g). When equilibrium had been established it was found that ¾ mole each of reactants AB and CD had been converted to AD and CB. There is no change in volume. The equilibrium constant for the reaction is

32. The half-life period for a first order reaction is 693 seconds. The rate constant of this reaction would be:

33. Which is correct about zero order reaction?

34. Which statement is incorrect about the catalyst?

35. A chemical reaction is catalyzed by X. Hence X

36. The activation energy of a reaction can be determined by

37. In a reaction A + 2B ⇌ 2C, 2.0 moles of ‘A’ 3 moles of ‘B’ and 2.0 moles of ‘C’ are placed in a 2.0 L flask and the equilibrium concentration of ‘C’ is 0.5 mol/L. The equilibrium constant (K) for the reaction is

38. Choose the incorrect statement from the followings

39. The value of Kp is greater than Kc for a gascous reaction when

40. Which of the following favours the reverse reaction in chemical equilibrium?

41. A gas bulb is filled with NO₂ gas and immersed in an ice bath at 0°C which becomes colourless after sometime. This colourless gas will be

42. The expression k = A ͤ Ea/RT is refered as

43. 4 moles of A re mixed with 4 moles of B, when 2 moles of C are formed at equilibrium according to the reaction A + B ⇌ C + D The value of equilibrium constant is

44. The equilibrium constant Kᵨ for the reaction PCl₅(g) ⇌ PCl₃(g) + CI₂(g) is 16. If the volume of the container is reduced to half of its original volume, the value of Kᵨ for the reaction at the same temperature will be

45. The amount of ₅₃I¹²⁸, (I₃₆ = 25 min) left after 50 min is

46. Give t₁/2 = 3 hr, then how many gram of a substance will remain after 18th hr from 300 gram of s substance

47. A student started to work on 100g of a compound whose half – life is 5 hours, how much compound is left after 25 hours

48. A reaction involving two different reactants can never be

49. The phenomenon of emission of visible light as result of chemical change is known as

50. 0.1 M HCl has pH = 1.0, it is about 100 times stronger than acetic acid. Then pH of acetic will be

51. Which of the following statement regarding catalyst is not true?

52. In a lime kiln, to get higher yield of CO₂, the measure that can be taken is:

53. Half-life period of 2nd order reaction is

54. A scientist prepared compound in laboratory. He found that is has two forms. One amorphous from A and another crystalline from C., Both A and C reacts with sulphuric acid. One possible prediction is that

55. For a chemical reaction A → B, it is found that the rate of reaction doubles when the concentration of A is increased four times. The order in A for this reaction is

56. 75% of first order reaction is complete in 30 minutes. What is the time required for 93.75% of the reaction (in minutes)?

57. The rate of reaction between two specific time intervals is called

58. Reaction with high activation energy

59. The rate of reaction is doubled for 10°C rise in temperature. The increase in the reaction rate as a result of temperature rise from 10°C to 100°C is

60. You store food in a fridge to prevent spoilage. Which factor are you applying to slow the rate of reaction?

61. A zero order reaction is one whose rate is independent of

62. When NH₃ is added to pure H₂O than concentration of any one of the following species is decreased

63. The rate of forward reaction is two times that of the reverse reaction at a given temperature and identical concentration, K equilibrium is

64. The mathematical reaction between the rate of reaction and the concentration of reactants is called x

65. For the reaction 2HI H₂ + I₂

66. Which of the following will not change the concentration of ammonia in the equilibrium N₂(g) + 3H₂(g) ⇌ 2NH₃(g); ∆H = -x kJ

67. An increase in concentration of reactants

68. The rate of reaction between A and B increases by a factor of 100, when the concentration with respect to A is increased 10 folds, the order of reaction w.r.t. A is

69. 0.1 M HCl has pH = 1..1, it is about 100 times stronger acid, pH of acetic acid is

70. A catalyst can be deactivated by the presence of even a small amount of impurity. This is called

71. When we increase the temperature, the rate of reaction increases because of

72. The half-life of a reaction is halved as the initial concentration of the reaction is doubled. The order of the reaction is

73. The active mass of 64 g of HI in a two liter flask would be

74. A reactions 50% complete is 2 hours and 75% complete in 4 hours order reaction is

75. 1 dm³ of 2 M CH₃COOH is mixed with 1 dm³ of 3 M ethanol to form ester. The decrease in the initial rate if each solution is diluted with an equal volume of water would be

76. Effect of temperature on reaction rate is given by

77. Pure H₂O has H₃O⁺ ion concentration of 10¯⁶ mole dm¯³ at 90°C is

78. Which of the following will not change the concentration of ammonia at the equilibrium?

79. Rate of a chemical reaction can be kept constant by

80. Large the surface area or the reactant molecules

81. For most of the chemical reactions the rate of reaction

82. Which statement is not correct?

83. Rate expression for NH³ synthesis is

84. The addition of a catalyst to a reaction

85. What is the time required for a first order reaction to be 99% complete, compared to the time taken for the reaction to be 90% complete?

86. With increase in 10°C temperature, the rate of reaction doubles. This increase in rate of reaction is due to

87. The rate of a first order reaction is 1.5 x 10¯² mol L¯¹ at 0.5 M concentration of the reactant. The half-life of the reaction is

88. The time taken for 90% of a first order reaction to complete is approximately

89. The reaction, 2SO₂(g) + O₂(g) → 2SO₃(g) is carried out in a 1 dm³ vessel and 2 dm³ vessel separately. The ratio of the reaction velocities will be

90. Which types of metals are usually used as catalyst?

91. H₂ + I₂ ⇌ 2HI Which one of the following will not affect the rate of this reaction?

92. The unit of rate constant for a zero order reaction is

93. Initially the rate to increase in concentration of products in a reaction is

94. If the rate of the reaction is equal to the rate constant, the order of reaction is

95. In a first order reaction, the concentration of the reactant, decreases from 0.8 M to 0.4 M in 15 minutes. The time taken for the concentration to change from 0.1 M to 0.025 M is

96. Which of the following statement about the catalyst is/are true?

97. A substance which retards the rate of reaction is called

98. A reaction A → B follows a second order kinetics. Doubling the concentration of A will increase the rate of formation of B by a factor or

99. Rancidity produced in butter can be decreased by adding Quinoline to the butter. The statement shows that

100. An example of autocatalytic reaction is

101. In zero order reaction, the rate in independent of

102. For a reaction A + B ⇌ C + D the partial presseres of A, B, C and D are 0.5, 1.00, 0.05 and 10 atm respectively at equilibrium. The value of kP for this reaction is

103. The hydrolysis of ester in alkaline medium is a

104. The concentration of reactants is increased by x, then equilibrium constant K becomes

105. All of the following are the postulates of Arrhenius theory of ionization except

106. The strongest base among the following is

107. The half period of ₆C¹⁴ is 5760 years, 100 mg of sample will be reduced to 25 mg in

108. Ammonium carbonate when heated to 200°C gives a mixture of NH₃ and CO₂ vapour with a density of 13.0. what is the degree of dissociation of ammonia carbonate?

109. The compounds A and B are mixed in equimolar proportion to form the products, A + B ⇌ C + D. At equilibrium, one third of A and B are consumed. The equilibrium constant for the reaction is

110. The addition of a catalyst to the reaction system

111. Which property of liquid is measured by polarimeter?

112. 4.5 moles each of hydrogen and iodine heated in a sealed ten liter vessel. At equilibrium 3 moles of HI were found. The equilibrium constant for H₂(g) + I₂(g) ⇌ 2HI(g) is

113. The half-lives of 2 samples are 0.1 and 0.4 seconds. Their initial conc. Are 200 and 50 respectively? What is is the order of the reaction?

114. Large the surface area of the reactant molecules

115. Rate of 1st order depends upon

116. In the equilibrium N₂ + 3H₂ ⇌ 2NH₃ + 22 kcal the formation of ammonia is favoured by

117. The enzyme which can catalyst the conversion of glucose to ethanol is

118. According to Law of Mass Action, rate of a chemical reaction is proportional to

119. The unit of ionic product of H₂O is

120. The dimensions of rate of reaction are

121. Hydrogen gas and iodine vapours combine to form HI at 425°C. The same composition of mixture is present if we start with decomposition of HI. It suggests

122. The PH of 10¯³ mol dm¯³ of aqueous solution of H₂SO₄ is

123. A chemical reaction is in equilibrium when

124. The chemical method used for determination of the rate of reaction is

125. Instantaneous rate of a chemical reaction is

126. In the reaction N₂(g) + O₂(g) ⇌ 2NO(g) ∆H = + 180.7 kJ. One increasing the temperature the production of NO

127. The rate of a reaction can be increased in general by all the factors except by

128. 3 mole of reactant A and one mole of reactant B are mixed in a vessel of volume 1 liter. The reaction taking place is A + B ⇌ 2C. If 1.5 mol of C is formed at equilibrium, the value of Kc is

129. The rate of reaction A + B → Products is given by the equation r = k [A][B] If B is taken in large excess, the order of the reaction would be

130. Choose the incorrect statement from the following

131. When KCIO₃ is heated, it decomposes into KCI and O₂. If some MnO₂ is added, the reaction goes much faster because

132. The average rate and instantaneous rate of a reaction are equal

133. For a reaction if Kp > Kc, the forward reaction is favoured by (T > 15 K)

134. Which of the following is the property of inhibitors?

135. The firs order rate constant of decomposition of N₂S₅ is 6.2 x 10¯⁴ sec. The initial pressure is 290 mm Hg and final is 360 mmHg. t/2 is

136. A solution with pH = 0, its H⁺ ion concentration is

137. When the rate of reaction is entirely independent of the concentration of reactant molecules then order of reaction is

138. For a given reaction t₁/2 = 1/ka. The order of reaction is

139. Of the following, which change will shift the reaction towards the product? I₂(g) ⇌ 2I(g) ∆H°t(298 K) = + 150 kJ

140. For a first order reaction, the half-life period is independent of

141. The rate of an irreversible reaction

142. Temperature coefficient of a reaction is 2. When temperature is increased form 30°C to 100°C, rate of the reaction increases by

143. Rate constant is case of first order reaction is

144. A catalyst increases rate of reaction by

145. The pH of buffer solution is 4.74. On adding 0.1 ml (0.00001M) HCl solution, the pH of solution will be

146. The rate constant of a reaction at temperature 200 K is 10 times less than the rate constant at 400 K. What is the activation energy (Eₐ) of the reaction?(R = gas constant)

147. Which one of the following is a buffer solution?

148. In a reaction A + B ⇌ C + D, the initial concentration of A and B were 0.9 mol dm¯³ each. At equilibrium the concentration of D was found to be 0.6 mol dm¯³. What is the value of equilibrium constant for the reaction?

149. The rate of a reaction that does not involve gases, does not depend upon

150. At 500 K the equilibrium constant for reaction cis-C₂H₂Cl₂ ⇌ trnas-C₂H₂Cl₂ is 0.6. At the same temperature, the equilibrium constant for the reaction trans- C₂H₂Cl₂ ⇌ cis- C₂H₂Cl₂ will be

151. An excess of aqeous AgNO₃ is added to aqueous barium chloride and precipitate is removed by filtration. What are the main ions in the filtrate

152. According to Le-Chatelier’s principal, adding heat to a solid and liquid in equilibrium will cause the

153. The ionic product of solution is greater than solubility product. The solution is

154. The rate of reaction

155. The rate of reaction determined at given time is called

156. If NH₃ gas is dissolved in H₂O, PH of the solution

157. Units of rate constant for the first and zero order reactions in terms of molarity, M units are respectively

158. Agcl dissolved with concentration (Z x 10¯²) Ksp will be

159. 75% of a first order reaction was completed in 32 minutes. When was 50% of the reaction completed?

160. The number if atoms or molecules whose concentration determines the rate of a chemical reaction is called

161. The reaction 2H₂O₂ → 2H₂O + O₂ is, r = k [H₂O₂]

162. The effect of increasing the pressure of the following equilibrium 2A + 3B ⇌ 3A + 2B is

163. The gaseous reaction A + B ⇌ 2C + D q most favoured at:

164. Under a given set of experimental condition, with increase in the concentration of the reactants the rate of

165. In equation, CHCI₃ + CI₂ → CCI₄ + HCI, the rate = k [CHCI₃][CI₂]½ the order of reaction is,