CHEM 0970 Lecture Notes - Lecture 6: Molar Mass, Sodium Chloride, Thermodynamics
Document Summary
Spontaneity does not mean that a reaction is fast. But: it is also so slow kinetically that it is essentially irrelevant. You could couple it with another process that is spontaneous. Catalysts affect the rate of a reaction, but it won"t change the spontaneity of one. Is it enthalpy? (exothermic reactions are spontaneous, endothermic are not) Examples: ice melts above 0c, water evaporates, nacl dissolves in water. Entropy is a measurement of how spread out a system"s energy is. Entropy is similar to disorder in a system. Energy spontaneously disperses from being localized to becoming spread out if it is not hindered from doing so. As the ice melts, the water molecules go from a highly ordered state (solid) to a less ordered state (liquid) The water molecules go from somewhat disorderly to a highly disorderly state. Nacl goes from a highly ordered state to a more disorderly one, where the ions are randomly dispersed.
