2. Solved Papers
  3. JEE Main & Advanced

JEE Main & Advanced AIEEE Solved Paper-2005

  • question_answer
    \[{{t}_{1/4}}\]can be taken as the time taken for the concentration of a reactant to drop to 3/4 of its Initial value. If the rate constant for a first order reaction is k, the \[{{t}_{1/4}}\] can be written as     AIEEE  Solved  Paper-2005

    A) 0.75/k  

    B)        0.69/k  

    C)        0.291k  

    D)        0.10/k

    Correct Answer: C

    Solution :

                      \[A\xrightarrow{{}}\Pr oduct\]
    Initially \[a\] 0
    After time t \[(a-x)\] \[x\]
    Afters \[{{t}_{1/4}}\] \[\left( a-\frac{a}{4} \right)\] \[\frac{a}{4}\]
    For first-order kinetics, \[k=\frac{2.303}{t}\log \left( \frac{a}{a-x} \right)\] \[\therefore \] \[k=\frac{2.303}{{{t}_{1/4}}}\log \frac{a}{\frac{3a}{4}}\] \[{{t}_{1/4}}=\frac{2.303\log \frac{4}{3}}{k}=\frac{0.29}{k}\]       


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