1. Tardigrade
  2. Question
  3. Chemistry
  4. Calculate the magnitude of ring strain energy in ( kJ / mol ) of cyclopropane from the following data Δ f H [ C 3 H ( g )]=55 ; Δ f H [ CH ( g )]=715 ; Δ f H [ H ( g )]=220 ; BE ( C - C )=355 ; BE ( C - H )=410 (All in kJ / mol ):

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Q. Calculate the magnitude of ring strain energy in $( kJ / mol )$ of cyclopropane from the following data
$\Delta_{ f } H \left[ C _{3} H ( g )\right]=55 ; \Delta_{ f } H [ CH ( g )]=715 ; $
$\Delta_{ f } H [ H ( g )]=220 ; BE ( C - C )=355 ; BE ( C - H )=410$
(All in $kJ / mol$ ):

Thermodynamics

Solution:

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$\Delta H _{4}=-$ B.E. $(3 C - C +6 C - H )+$ Ring strain energy (RSE)
$=\Delta H _{1}-\Delta H _{2}-\Delta H _{3} $
$ R.S.E. =\Delta H _{1}-\Delta H _{2}-\Delta H _{3}+\text { B.E. }(3 C - C +6 C - H )$
$=55-2145-1320+(3 \times 355+6 \times 410)$
$=115\, kJ / mol$