what happen when activation energy of a chemical reaction becomes equal to RT?

“It means if Ea=RT then rate constant become about 37% of the Arrhenius constant.

The energy of activation for a reaction is 100 kJ mol–1. Presence of a catalyst lowers the energy of activation by 75%.What will be effect on rate of reaction at 20ºC, other things being equal?

SOLUTION: The Arrhenius equation is

In Arrhenius equation for a certain reaction, the value of A and Ea (activation energy) are 4 × 10^13 sec–1 and 98.6 kJ mol–1 respectively. At what temperature, the reaction will have specific rate constant 1.1 × 10^–3 sec–1?

SOLUTION: According to Arrhenius equation

Cu64 (Half life=22.8 hours) decay by beta emission (38%), beta+ emission (19%) and electron capture (43%). write the decay product and calculate Half lives for each of the decay process. [IIT 2002]

SOLUTION:  

(1):

 (2)  Above are parallel reactions occurring from Cu⁶⁴   

T₁ T₂ and T₃ are the corresponding partial half lives and also K= K₁ + K₂ + K₃ (for parallel reaction) 

Write correct Nernst equation for the given galvanic cell containing both the electrodes are M/M (insoluble) salt at 25°c.: Ag(s)|AgCl(s)| KCl(M) || KBr (M)|AgBr(s)|Ag(s): [Given Ksp(AgCl) and Ksp(AgCl)]

Important thing :

For concentrated cell both electrodes are same so E not cell is always zero  and Qc is always less than one.

You should first assume any one is the cathode and the other one  is the anode. Then you can calculate the theoretical emf:

(1)  If the emf > 0, then that reaction will be spontaneous and it means you got the right cathode and right anode.

 (2) If the calculated emf < 0, it means that that reaction is not spontaneous, which means that the reverse reaction is spontaneous; that happens if you exchange the cathode and anode.