Advertisement

State any one condition under which a bimolecular reaction may be kinetically first order.


 any one of reactant is present in excess of amount in reaction.

CH3COOC2H5 + H2O ----> CH3COOH + C2H5OH

water is present in excess of amount.

135 Views

Advertisement
The difference in energy of activation for uncatalysed reaction and catalysed reaction is 20 kJ/mol. How many times the rate constant of catalysed reaction will increase over the uncatalysed reaction?

According to the Arrhenius equation 
k= Ae-Ea/RT
where Ea is activation energy, T is temperature.

k1 = Ae-Ea/RTk2 = Ae-Ea(c)/RTlog k2k1 = Ea-Ea(c)2.303 RTlog k2k1 = 20,00002.303×8.314×300 = 3.48k2k1 = 3020

Thus, the reaction rate has increased nearly by 3020.
120 Views

A certain reaction is 50% complete in 20 minutes at 300 K and the same reaction is again 50% complete in 5 minutes at 350 K. Calculate the activation energy if it is a first order reaction. [R = 8.314 J K–1 mol–1, log 4 = 0.602].

BY using the half life equation, we get

t1/2 = 20 min k1 = 0.693t1/2 = 0.69320min-1k2 = 0.693t1/2 = 0.6935min-1

log k2k1 = Ea2.303 R1T1-1T2


or        

log 9.69350.69320 = Ea2.303 × 8.3141300-1350

or                          

              Ea = 19.147 × 350 × 300 × log 450        = 19.147 × 7 × 300 × 0.60211000         = 24.2 kJ mol-1.
2689 Views

The reaction A + B → C has zero order. What is the rate equation?

Rate of equation 
rate = k[A]0

121 Views

The rate of a particular reaction triples when temperature changes from 50°C to 100°C. Calculate the activation energy of the reaction. [log 3 = 0.4771 (R = 8.314 ] K–1mol–1)

By using the Arrhenius equation we get 

log k2k1 = Ea2.303 RT1T1-1T2log 3 = Ea2.303 × 8.314 1323-1373  Ea =  0.4771 × 19.147 × 323 × 37350       = 1100579.750 = 22011.59 J                = 220.12 kJ mol-1.
554 Views

Advertisement