Chemical Kinetics - Result Question 78

####77. While studying the decomposition of gaseous N2O5, it is observed that a plot of logarithm of its partial pressure versus time is linear. What kinetic parameters can be obtained from this observation?

(1985, 2M)

Show Answer

Solution:

  1. For a first order process : ln[A]0[A]=ktln[A]=ln[A]0kt

If the reactant is in gaseous state

and kt1/10ln[A]0[A]0/10=ln10

Therefore, t1/8t1/10=ln8ln10=log8=3log2=3×0.3=0.9

t1/8t1/10×10=0.9×10=9

lnp=lnp0kt

where p is the partial pressure of reactant remaining unreacted at instant ’ t ’ and p0 is its initial partial pressure.

Also, from equation (i), lnpvst would give a straight line. Therefore, decomposition of N2O5 following first order kinetics.



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक