61. In the Arrhenius plot of $$\ln \,k\,Vs\frac{1}{T},$$   a linear plot is obtained with a slope of $$ - 2 \times {10^4}K.$$   The energy of activation of the reaction $$\left( {{\text{in}}\,kJ\,mol{e^{ - 1}}} \right)$$    is ( $$R$$ value is $$8.3\,J\,{K^{ - 1}}\,mo{l^{ - 1}})$$

A 83
B 166
C 249
D 332
Answer :   166
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62. For the reaction, $${N_2} + 3{H_2} \to 2N{H_3},$$     if $$\frac{{d\left[ {N{H_3}} \right]}}{{dt}} = 2 \times {10^{ - 4}}mol\,{L^{ - 1}}{s^{ - 1}},$$       the value of $$\frac{{ - d\left[ {{H_2}} \right]}}{{dt}}$$   would be

A $$3 \times {10^{ - 4}}mol\,{L^{ - 1}}{s^{ - 1}}$$
B $$4 \times {10^{ - 4}}mol\,{L^{ - 1}}{s^{ - 1}}$$
C $$6 \times {10^{ - 4}}mol\,{L^{ - 1}}{s^{ - 1}}$$
D $$1 \times {10^{ - 4}}mol\,{L^{ - 1}}{s^{ - 1}}$$
Answer :   $$3 \times {10^{ - 4}}mol\,{L^{ - 1}}{s^{ - 1}}$$
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63. The differential rate law for the reaction
$${H_2} + {I_2} \to 2HI$$    is

A $$ - \frac{{d\left[ {{H_2}} \right]}}{{dt}} = - \frac{{d\left[ {{I_2}} \right]}}{{dt}} = \frac{{d\left[ {HI} \right]}}{{dt}}$$
B $$\frac{{d\left[ {{H_2}} \right]}}{{dt}} = \frac{{d\left[ {{I_2}} \right]}}{{dt}} = \frac{1}{2}\frac{{d\left[ {HI} \right]}}{{dt}}$$
C $$\frac{1}{2}\frac{{d\left[ {{H_2}} \right]}}{{dt}} = \frac{1}{2}\frac{{d\left[ {{I_2}} \right]}}{{dt}} = - \frac{{d\left[ {HI} \right]}}{{dt}}$$
D $$ - 2\frac{{d\left[ {{H_2}} \right]}}{{dt}} = - 2\frac{{d\left[ {{I_2}} \right]}}{{dt}} = \frac{{d\left[ {HI} \right]}}{{dt}}$$
Answer :   $$ - 2\frac{{d\left[ {{H_2}} \right]}}{{dt}} = - 2\frac{{d\left[ {{I_2}} \right]}}{{dt}} = \frac{{d\left[ {HI} \right]}}{{dt}}$$
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64. At $${518^ \circ }C,$$  the rate of decomposition of a sample of gaseous acetaldehyde, initially at a pressure of $$363\,Torr,$$  was $$1.00\,Torr\,{S^{ - 1}}$$   when $$5\% $$  had reacted and $$0.5\,Torr\,{S^{ - 1}}$$   when $$33\% $$  had reacted. The order of the reaction is :

A 2
B 3
C 1
D 0
Answer :   2
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65. In Arrhenius plot, intercept is equal to

A $$\frac{{ - {E_a}}}{R}$$
B $$\ell n\,A$$
C $$\ell n\,K$$
D $${\log _{10}}A$$
Answer :   $$\ell n\,A$$
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66. In a reaction, $$2HI \to {H_2} + {I_2},$$    the concentration of $$HI$$  decreases from $$0.5\,mol\,{L^{ - 1}}$$   to $$0.4\,mol\,{L^{ - 1}}$$   in 10 minutes. What is the rate of reaction during this interval?

A \[5\times {{10}^{-3}}\,M\,{{\min }^{-1}}\]
B \[2.5\times {{10}^{-3}}\,M\,{{\min }^{-1}}\]
C \[5\times {{10}^{-2}}\,M\,{{\min }^{-1}}\]
D \[2.5\times {{10}^{-2}}M\,{{\min }^{-1}}\]
Answer :   \[5\times {{10}^{-3}}\,M\,{{\min }^{-1}}\]
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67. For the reaction $$A + 2B → C,$$   rate is given by $$R = \left[ A \right]{\left[ B \right]^2}$$   then the order of the reaction is

A 3
B 6
C 5
D 7
Answer :   3
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68. The rate of reaction between two reactants $$A$$ and $$B$$ decreases by a factor of 4, if the concentration of reactant $$B$$ is doubled. The order of this reaction with respect to reactant $$B$$ is

A $$-1$$
B $$-2$$
C $$1$$
D $$2$$
Answer :   $$-2$$
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69. What will be the half-life of the first order reaction for which the value of rate constant is $$200\,{s^{ - 1}}?$$

A $$3.46 \times {10^{ - 2}}\,s$$
B $$3.46 \times {10^{ - 3}}s$$
C $$4.26 \times {10^{ - 2}}\,s$$
D $$4.26 \times {10^{ - 3}}\,s$$
Answer :   $$3.46 \times {10^{ - 3}}s$$
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70. In the reaction, $$A + 2B \to 6C + 2D,$$     If the initial rate $$ - \frac{{d\left[ A \right]}}{{dt}}$$   at $$t=0$$  is $$2.6 \times {10^{ - 2}}M\,{\sec ^{ - 1}},$$    what will be the value of $$\frac{{d\left[ B \right]}}{{dt}}$$   at $$t = 0?$$

A $$8.5 \times {10^{ - 2}}M\,{\sec ^{ - 1}}$$
B $$2.5 \times {10^{ - 2}}M\,{\sec ^{ - 1}}$$
C $$5.2 \times {10^{ - 2}}M\,{\sec ^{ - 1}}$$
D $$7.5 \times {10^{ - 2}}M\,{\sec ^{ - 1}}$$
Answer :   $$5.2 \times {10^{ - 2}}M\,{\sec ^{ - 1}}$$
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