"The first law of thermodynamics is a formulation of the law of conservation of energy in the context of thermodynamic processes."
The law that states that energy cannot be created or destroyed, only transferred or converted. It also includes the definition of internal energy, work, and heat.
System and surroundings: The system is the portion of the universe being studied, while the surroundings include everything else. The boundary is the interface between the two.
Internal energy: This is the sum of all the kinetic and potential energy possessed by the particles that compose the system.
Enthalpy: This is a thermodynamic property that represents the sum of the internal energy and the product of the pressure and volume.
Heat and work: Heat is the transfer of energy due to a temperature difference, while work is the transfer of energy due to a force acting over a distance.
Heat capacity: This is the amount of heat required to raise the temperature of a substance by a certain amount.
State functions: These are thermodynamic properties that depend only on the current state of the system and not on how it got there.
Reversible and irreversible processes: A reversible process is one that can be reversed without any net change to the system or the surroundings, while an irreversible process is one that cannot.
Heat transfer mechanisms: These include conduction, convection, and radiation.
Thermodynamic cycles: These are processes that return the system to its initial state after completing a sequence of steps.
The first law of thermodynamics: This states that the total energy of the universe is constant, and that energy can be transferred from one form to another, but cannot be created or destroyed.
Adiabatic processes: These are processes that occur without any heat transfer between the system and the surroundings.
Joule’s law: This relates the internal energy of an ideal gas to its temperature.
Thermodynamic potentials: These are state functions that are useful for describing equilibrium states of a system.
Chemical kinetics: This is the study of the rates and mechanisms of chemical reactions.
Equilibrium: This is the state at which the rates of the forward and reverse reactions are equal, and no further net change in the system occurs.
The law of conservation of energy: This is the basic principle of the first law and states that the total energy of a closed system remains constant.
The internal energy: This is the sum of the kinetic and potential energies of the particles that make up a system. The first law states that the internal energy of a system is conserved in a closed system.
The heat transfer: Heat is a form of energy and can be transferred from one system to another. The first law states that the amount of heat transferred into a system equals the amount of work done by the system.
The work done: Work is a measure of the energy required to move an object against a force. The first law states that the work done by a system is equal to the change in its internal energy.
Enthalpy: Enthalpy is the heat content of a system at a constant pressure. The first law states that the change in enthalpy of a system is equal to the heat transferred at constant pressure.
Heat capacity: The heat capacity is the amount of heat required to increase the temperature of a system by one degree. The first law states that the heat capacity of a system is proportional to its internal energy.
Specific heat: The specific heat is the amount of heat required to raise the temperature of one unit mass of a substance by one degree. The first law states that the specific heat of a substance is proportional to its internal energy.
Adiabatic process: An adiabatic process is one that occurs without any heat transfer between a system and its surroundings. The first law states that the change in internal energy of an adiabatic process is equal to the work done by the system.
Isobaric process: An isobaric process occurs at a constant pressure. The first law states that the change in enthalpy of an isobaric process is equal to the heat transferred at constant pressure.
Isochoric process: An isochoric process occurs at a constant volume. The first law states that the change in internal energy of an isochoric process is equal to the heat transferred at constant volume.
Reversible process: A reversible process is one in which a system can be returned to its original state without any net change in the system or its surroundings. The first law states that the internal energy change of a reversible process is equal to the work done by the system.
Irreversible process: An irreversible process is one in which a system cannot be returned to its original state without some net change occurring. The first law states that the internal energy change of an irreversible process is greater than the work done by the system.
"It distinguishes in principle two forms of energy transfer, heat and thermodynamic work for a system of a constant amount of matter."
"The law defines the internal energy of a system, an extensive property for taking account of the balance of these energies in the system."
"Energy cannot be created or destroyed, but it can be transformed from one form to another."
"In an isolated system, the sum of all forms of energy is constant."
"An equivalent statement is that perpetual motion machines of the first kind are impossible."
"Work done by a system on its surroundings requires that the system's internal energy be consumed."
"The amount of internal energy lost by that work must be resupplied as heat by an external energy source or as work by an external machine acting on the system to sustain the work of the system continuously."
"The ideal isolated system, of which the entire universe is an example, is often only used as a model."
"Many systems in practical applications require the consideration of internal chemical or nuclear reactions, as well as transfers of matter into or out of the system."
"For such considerations, thermodynamics also defines the concept of open systems, closed systems, and other types."
"It distinguishes in principle two forms of energy transfer, heat and thermodynamic work."
"Energy cannot be created or destroyed, but it can be transformed from one form to another."
"In an isolated system, the sum of all forms of energy is constant."
"An equivalent statement is that perpetual motion machines of the first kind are impossible."
"Work done by a system on its surroundings requires that the system's internal energy be consumed."
"The amount of internal energy lost by that work must be resupplied as heat by an external energy source or as work by an external machine acting on the system to sustain the work of the system continuously."
"The ideal isolated system, of which the entire universe is an example, is often only used as a model."
"Many systems in practical applications require the consideration of internal chemical or nuclear reactions, as well as transfers of matter into or out of the system."
"For such considerations, thermodynamics also defines the concept of open systems, closed systems, and other types."