Question

You decide you should fix some stuff around your home since you are stuck there. While doing some pretty awesome and sophisticated changing-the-light-bulb work, your dog’s start freaking out about a squirrel and bump your ladder. You fall and hurt your shoulder. Luckily, you have a chemical hot pack in your medicine cabinet. You activate it, it warms up, you put it on your shoulder, and then you settle in for some chemistry investigations. (Background)

You look up the chemical mechanism for the reaction in the hot pack and find it is just a solvation process – when you activate the pack, you break a membrane and the magnesium sulfate is able to interact with the water on the other side of the membrane. Based on your experience, what do you know about the signs of AH and of AG for this process? Use at least two complete sentences to explain your answer.