Acid is a substance that produces protons when dissolved in water. In other words an acid is something sour an example of it is fatty acids. There also strong acids, a base is also substance that produces. An example of a base is sodium hydroxide,a base is something bitter.Tempature is a measure of random motion. Heat is a flow of energy, heat and tempature are not the same. Also exothermic and endothermic have a different meaning. Exothermic is the outside the system and edothermic is inside which were the heat flows. The study of energy is called thermodynamics,the law is energy of the universe is constant.