NEET Sample Paper NEET Sample Test Paper-85

  • question_answer
    The rate of a reaction A doubles on increasing the temperature from 300 to 310 K. By how much, the temperature of reaction B should be increased from 300 K so that rate doubles if activation energy of the reaction B is twice to that of reaction A.

    A)  9.84 K 

    B)        4.92 K

    C)  2.45 K 

    D)        19.67 K

    Correct Answer: B

    Solution :

    [b] \[\log \frac{{{K}_{2}}}{{{K}_{1}}}=\frac{E}{2.303R}\left[ \frac{{{T}_{2}}-{{T}_{1}}}{{{T}_{1}}{{T}_{2}}} \right]\] For reaction A - Given,\[\frac{{{K}_{2}}}{{{K}_{1}}}=2,\]\[{{T}_{1}}=300\,\,K,\]\[{{T}_{2}}=310\,\,K\] \[\log 2=\frac{E}{2.303\,R}\left[ \frac{1}{300}-\frac{1}{310} \right]\]                     ?(i) For reaction B - Given, \[\frac{{{K}_{2}}}{{{K}_{1}}}=2,\]\[E=2E,\]\[{{T}_{1}}=300\,\,K,\]\[{{T}_{2}}=?\] \[\log 2=\frac{2E}{2.303\,R}\left[ \frac{1}{300}-\frac{1}{{{T}_{2}}} \right]\]                    ?(ii) From equation (i) and (ii), \[\frac{2E}{2.303\,R}\left[ \frac{1}{300}-\frac{1}{{{T}_{2}}} \right]=\frac{E}{2.303\,R}\left[ \frac{1}{300}-\frac{1}{310} \right]\] \[\Rightarrow \]\[2\left[ \frac{1}{300}-\frac{1}{{{T}_{2}}} \right]=\frac{310-300}{300\times 310}\] \[\Rightarrow \]\[{{T}_{2}}=304.92\,\,K\] \[{{T}_{1}}=300\,K,\]\[{{T}_{2}}=304.92\,K\] \[\Delta T={{T}_{2}}-{{T}_{1}}=4.92\,K.\]


You need to login to perform this action.
You will be redirected in 3 sec spinner