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The rate of reaction quadruples when the temperature changes from 293 K to 313 K. Calculate the energy of activation of the reaction that it does not change with temperature.

According to Arrhenius equation,
logK2K1 = Ea2.303 R1T1-1T2T1 = 293 K,  T2 = 313 Klog 41 = Ea2.303 × 8.314 J mol-1K-11293K-1313K   log 4 = Ea2.303 × 8.314 J mol-1×20293 × 313Ea = 0.6021 × 2.303 × 8.314 × 293 × 31320     = 5.2863 × 104J mol-1 = 52.863 kJ mol-1
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The rate constant for the first order decomposition of H2O2 is given by the following equation:
log k = 14.34 – 1.25 x 104 k/T
Calculate Efor this reaction and at what temperature will its half period be 256 minutes.



Using arrhenius equation 

log K = log A-Ea2.303R-1T

Comparing this equation with

log K = 14.34-1.25×104KTgivesEa2.303R=1.25×104KEa =1.25×104K×2.303×8.314 J mol-1K-1or Ea = 239.339 J mol-1 =239.339 kJ mol-1.

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The decomposition of hydrocarbon follows the equation
k = (4.5 x 1011 s–1) e–28000K/T
Calculate Ea


The given equation is 

K=(4.5 × 1011 S-1) e-28000k/Tlog K = log A - EaRTor  EaR =28000 Kor  Ea = 28000×R=28000×8.314 = 232792 J mol-1 =232.79 kJ mol-1
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The decomposition of A into product has value of K as 4.5 x 103 S–1 at 10°C and energy of activation 60 kJ mol–1. At what temperature would K be 1.5 x 104 S–1

K1 = 4.5 x 103 S–1 ,  T1 = 273 + 10 = 283 K
Ea = 60 kJ mol–1 T2 = ?
K2 = 1.5 x 104S–1
We know that

logK2K1 = Ea(T2-T1)2.303R T1T2log1.5 × 1044.5×103 = 60(T2-283)2.303 × 8.314 × 283 × T2log 15045 = 60(T2×283)5418.64 T2log 150 - log 45 = 60T2-169805418.64 T22.1761 - 1.6532 = 60T2-169805418.64 T20.5229 = 60T2-169805418.64 T22833.4 T2 = 60T2-169802833.4 T2 = 60T2 = -169802773.4 T2 = 16980T2 = 169802733.4 = 6.1 K

 
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