Question
An exothermic chemical reaction proceeds by two stages. Reactants \[\xrightarrow{\text{stage}\,1}\] Intermediate \[\xrightarrow{\text{stage}\,2}\] Products
An exothermic chemical reaction proceeds by two stages. Reactants \[\xrightarrow{\text{stage}\,1}\] Intermediate \[\xrightarrow{\text{stage}\,2}\] Products
The activation energy of stage 1 is \[50\,kJ\,mo{{l}^{-1}}.\] The overall enthalpy change for the reaction is \[-100\,kJ\,mo{{l}^{-1}}.\] Which diagram could represent the energy level diagram for the reaction?
A.
B.
C.
D.
Answer :
Solution :
Diagram (C) represents exothermic reaction with
$$\eqalign{ & {E_a} = 200 - 150 \cr & \,\,\,\,\,\,\,\, = 50\,kJ\,mo{l^{ - 1}} \cr & {\text{and}}\,\,\Delta H = 50 - 150 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = - 100\,kJ\,mo{l^{ - 1}} \cr} $$
Diagram (C) represents exothermic reaction with
$$\eqalign{ & {E_a} = 200 - 150 \cr & \,\,\,\,\,\,\,\, = 50\,kJ\,mo{l^{ - 1}} \cr & {\text{and}}\,\,\Delta H = 50 - 150 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = - 100\,kJ\,mo{l^{ - 1}} \cr} $$