Give the 3 Importance and 3 applications of Enthalphy
Measuring the change in enthalpy allows us to determine
1) whether a reaction was endothermic (absorbed heat, positive change in enthalpy) or exothermic (released heat, a negative change in enthalpy.)
2) It is used to calculate the heat of reaction of a chemical process.
Change in enthalpy can apply to refrigerators and hand warmers. In a fridge, refrigerants such as Freon are evaporated. The enthalpy of vaporization (liquid to gas energy change) is equivalent to the coldness of your food.
Some people use chemical heat packs (hand warmers) outside. When you shake the pack, it begins to heat your hands. Various reactants inside the pack are exposed to air. This is another example of change in enthalpy.