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Chemical Kinetics

Question
CBSEENCH12006147

The rate of the chemical reaction doubles for an increase of 10 k in absolute temperature from 298 K. Calculate Ea.

Solution
Given that initial temperature, T1 = 298 K 
Final temperature, T2 = 298 + 10 = 308 K
Rate of chemical reaction will increase with raise of rate constant so that take 
Initial value of rate constant k1 = k 
find rate constant, k2 = 2k 
Also, R = 8.314 J K−1 mol−1
Use Arrhenius equation
According to Arrchenium equation,
    log k2k1 = Ea2.303 R1T1-1T2
        k2k1 = 2,   T1 = 298 K,   T2 = 298 + 10 = 308 k    R = 8.314 J k-1 mol-1
      log 2 = Ea2.303 × (8.314 J K-1 mol-1)                                                            1298 k-1308 k
or  0.3010 = Ea2.303 × 8.314 × 10298 × 308

        Ea = 0.3010×2.303×8.314×298×30810J mol-1

     Ea = 0.3010×2.303×8.314×298×30810×100kJ mol-1      = 52.89 kJ mol-1