Glossary of terms
A-F
Adiabatic system: An adiabatic system can have no exchange of matter, and energy can only be exchanged in the form of work between the system and surroundings
Closed system: A closed system is one where there can be no exchnage of matter, but energy in either the form of heat or work may be exchanged between the system and surroundings.
Endothermic: an endothermic reaction has a positive value for ΔH and energy is transferred from the surroundings to the system in the form of heat
Exothermic: an exothermic reaction has a negative value for ΔH and energy is transferred from the system to the surroundings in the form of heat
Extensive property: a property which is dependent upon the amount of ‘stuff’ you have, such as mass, volume, and enthalpy.
G-M
-Gibbs’ free energy (G): the amount of non expansion work which can be derived from a system, if the value of Gibbs free energy change for a process is negative the reaction is spontaneous.
Heat: a mode of transfer of energy which causes chaotic (or non-uniform) motion of the system or surroundings
Heat capacity: see specific heat capacity or molar heat capacity
Intensive property: a property which is independent of the amount of ‘stuff’ you have, such as temperature, molar volume, and molar enthalpy.
Isobaric: at constant pressure.
Isochoric: at constant thermal.
Isolated system: An isolated system is one where there can be no exchange of either matter or energy between the system and surroundings
Isothermal: at constant temperature.
Macrostate: the overall way a system looks, a macrostate often has multiple ways (microstates) to achieve this state .
Microstate: the way a system looks as if we can uniquely identify individual particles.
Molar heat capacity: the energy in the form of heat requred to raise the temperature of 1 mol of a substance by 1 K
N-S
Open system: In an open system both matter and energy may be exchanged between the system and surroundings.
Path function: a path function is one which depends upon the route taken to go between the initial and final states. Functions such as work are path functions.
reversible: when a process is reversible in thermodynamics it is in equilibrium at all times and any changes which occur are infinitessimally small.
Specific heat capacity: the energy in the form of heat requred to raise the temperature of 1 kg (or 1 g) of a substance by 1 K
State function: a state function is one where only the current state of the system matters, for functions such as enthalpy change we only need to know the initial and final states and not how it got between those states.