The gas phase reaction: cl(g) + hbr(g) →hcl(g) + br(g)has an overall enthalpy change of −66 kj. the activation energy for the reaction is 7 kj. a) draw the potential energy curve for the reaction and label ea, ∆e, and the activated complex or transition state. b) draw the potential curve for the reverse reaction. what is ea? what is ∆e?

See the picture attached

Explanation:

a) The original reaction has a negative enthalpy change, that means the reaction is exothermic, that is, the energy of the products is lower than the energy of the reactants (see picture). In the figure, ∆E is referred as energy released.

b) In the reverse reaction, the magnitude of ∆E is the same of the original reaction, but now the reaction is endothermic, so ∆E is positive, then ∆E = 66 kJ. In the figure, ∆E is referred as energy absorbed. As can be seen in the picture, the activation energy now is the addition of the magnitude of the enthalpy change and activation energy of the original reaction, that is, Ea = 7 kJ + 66 kJ = 73 kJ.

it's all four options.