The value of Ea for the potential energy diagram in Image 2 is?

Question

The value of Ea for the potential energy diagram in Image 2 is? 

1. 25 kJ
2. - 65 kJ
3. - 40 kJ
4. 40 kJ
5. - 25 kJ

IMAGE 2

Answer 1

The Ea is the the amount of energy needed to go from the reactants (40) to the peak (80) so it would be 40 kJ (positive), i.e. answer #4.