question_answer

The temperature dependence of rate constant (k) of a chemical reaction is written in terms of Arrhenius equation \[k=A{{e}^{-{{E}_{a}}/RT}}\]. Activation energy \[({{E}_{a}})\] of the reaction can be calculated by ploting

A)  \[\log \,k\,vs\,T\]     

B)         \[\log \,k\,vs\,\frac{1}{T}\]        

C)         \[k\,\,vs\,\,\,T\]        

D)         \[k\,\,vs\,\,\,\frac{1}{\log T}\]

Correct Answer: B

Solution :

\[k=A{{e}^{-{{E}_{a}}/RT}}\] \[\log k=\log A-\frac{{{E}_{a}}}{2.303RT}\] Comparing this equation with straight line \[y=mx+c\] \[y=\log k\] and \[x=\frac{1}{T}\]. \[\therefore \]\[{{E}_{a}}\] is calculated with the help of slope by plotting the curve between log k and \[\frac{l}{T}\].