Answer:
200kJ, 50KJ = H
Explanation:
Activation energy is basically the amount of energy it takes for the chemical reaction to happen. So if the reactant takes 50kJ, and adding 200KJ will begin the transition state where it will convert to a product.
So just do top - initial. 250-50 = 200
The H is the difference in energy between the reactants and product, which in this case is 100-50 = 50, so do products-reactants.
You are correct to assume that this is an endothermic reaction since it still retains energy (the proper meaning of endo is to absorb heat, but for the sake of explanation, imma say retain), but if the difference of product-reaction is negative, than it is exothermic (release energy). I'm guessing you already know that since you didn't need help with that.
Hope that helps
