The NIST Chemistry WebBook has more information. If the enthalpy of formation of each reactant and product is known, the amount of energy produced or absorbed can be calculated. With this information, you can predict whether a reaction will be exothermic or endothermic. The Enthalpy change for a reaction is the sum of the enthalpy changes for a series of reactions that add up to the overall reaction. This assignment must be turned in by the beginning of class tomorrow to receive credit.
States of matter are good examples of entropy.
Crystalline solids have a repeating pattern - a high degree of order. The particles of a liquid are more disordered than those of a solid. Gas particles, moving almost totally at random, have the largest entropy of all. The symbol D S represents change in entropy. A positive value means an increase in the degree of disorder.