A reaction can be spontaneous regardless of the sign of ΔH. For example, commercial hot packs and cold packs both use spontaneous reactions, but in a hot pack heat flows out (ΔH<0) and in a cold pack heat flows in (ΔH>0). While enthalpy plays a role in spontaneity, it is not the only factor. In this section, we will introduce a new thermodynamics state function, entropy (S). Together, the entropy and enthalpy changes during a reaction process dictate whether or not a reaction is spontaneous.
2.1: Alkane nomenclature
2.2: Alkene and alkyne nomenclature
2.3: Common names for branching substituents
2.4: Cyclic hydrocarbon nomenclature
2.5: Identifying functional groups
2.6: Naming low-priority functional groups (ethers, sulfides, and halides)
2.7: High priority functional groups
2.8: Common names