Example 5:
Cyclopropane (C3H6) at room temperature has a ring structure. When it is heated, the ring opens up and cyclopropane isomerizes to propylene.
The reaction takes place in a first order manner. Therefore, the rate law for the reaction is, rate (r) = k [C3H6]1
fig 6.5 - First Order Reaction: Concentration versus time profile
The above figure is an example of the first order reaction. The rate of the reaction depends on the concentration of the reactant. Initially the rate is fast and then it slows down as the concentration of the reactant falls.

