1. Tardigrade
  2. Question
  3. Chemistry
  4. The polymerization of propene to linear polypropene is represented by the reaction <img class=img-fluid question-image alt=image src=https://cdn.tardigrade.in/img/question/chemistry/024ce993cc1e97189001f4836eb6622c-.png /> Where n has large integral value, the average enthalpies of bond dissociation for (C=C) and (C-C) at 298 K are +590 and +331 kJ mol -1, respectively. The enthalpy of polymerization is -360 kJ -1. Find the value of n

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. The polymerization of propene to linear polypropene is represented by the reaction
image
Where $n$ has large integral value, the average enthalpies of bond dissociation for $(C=C)$ and $(C-C)$ at $298 \,K$ are $+590$ and $+331 \,kJ \,mol ^{-1}$, respectively. The enthalpy of polymerization is $-360 \,kJ ^{-1}$. Find the value of $n$

Thermodynamics

Solution:

Energy released $=$ Energy due to formation of two single bonds
$=2 \times 331=662 \,kJ \,mol ^{-1}$ of propene
$\Delta H$ polymerization $/ mol =590-662=$
$-72\, kJ \,mol ^{-1}$
$\Delta H$ polymerisation $=-72 \times n=-360$
$n=5$