The diagram shows the potential energy changes for a reaction pathway. Part 1: does the diagram illustrate an endothermic or an exothermic reaction? Give reasons in support of your answer.
Part 2: Describe how you can determine the total change in enthalpy and activation energy from the diagram and if each is positive or negative.

Absalon adds 1 g of salt to 1 l of room temperature water (25 °c). then, he starts a timer and observes what happens. he notices that it takes 1 minute for the salt to dissolve. he decides to repeat his experiment, and he adds 1 g of salt to another 1 l of room temperature water (25 °c). after he adds the salt, he starts a timer. but, instead of watching the salt dissolve, he stirs the salt and water with a spoon until it dissolves. he notices that it only takes 30 seconds for the salt to dissolve in his second experiment. why does the salt dissolve faster in absalon's second experiment? stirring the salt and water increases the polarity of the water molecules, which causes the ionic bonds of the salt to break. stirring the salt and water increases particle motion, which causes more collisions to occur between the water and salt. stirring the salt and water increases the surface area of the water, which causes more collisions to occur between the water and salt. stirring the salt and water increases the pressure on the solution, which causes the ionic bonds of the salt to break.