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Energetics key terms
Study Energetics with curriculum-aligned Key Terms resources, practice links, and exam-focused support.
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key terms
Resource type
Topic
Energetics
Key terms
Enthalpy (H)
A thermodynamic quantity equivalent to the total heat content of a system.
Exothermic reaction
A reaction that releases heat, resulting in a negative enthalpy change.
Enthalpy (H)
A thermodynamic quantity equivalent to the total heat content of a system, defined as H = U + PV, where U is internal energy, P is pressure, and V is volume.
Standard Enthalpy Change (ΔH°)
The change in enthalpy when one mole of a substance is formed from its elements in their standard states under standard conditions (298 K and 1 atm).
Enthalpy (H)
A measure of the total energy of a thermodynamic system, including internal energy and the energy associated with pressure and volume.
Activation Energy (Ea)
The minimum amount of energy required to initiate a chemical reaction.
Enthalpy (H)
A measure of the total energy of a thermodynamic system, including internal energy and the energy required to make room for it by displacing its environment.
Standard Conditions
A set of conditions defined as 1 atm pressure and a specified temperature, usually 298 K (25 °C).
Calorimetry
The measurement of heat changes in physical and chemical processes.
Enthalpy
A measure of the total energy of a thermodynamic system, often associated with heat changes at constant pressure.
Calorimeter
An instrument used to measure the amount of heat involved in a chemical reaction or physical process.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, typically measured in kJ/mol.
Exothermic Reaction
A reaction that releases energy in the form of heat to its surroundings.
Endothermic Reaction
A reaction that absorbs energy from its surroundings, resulting in a decrease in temperature.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, typically measured in kJ/mol.
Calorimeter
An instrument used to measure the amount of heat involved in a chemical reaction or physical change.
Enthalpy (H)
A thermodynamic quantity equivalent to the total heat content of a system.
Calorimetry
The measurement of heat changes in physical and chemical processes.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, measured in kJ/mol.
Standard enthalpy of formation (ΔHf°)
The enthalpy change when one mole of a compound is formed from its elements in their standard states.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, measured in kJ/mol.
Standard enthalpy of formation (ΔHf°)
The enthalpy change when one mole of a compound is formed from its elements in their standard states.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, measured in kJ/mol.
Combustion
A chemical reaction that occurs when a substance reacts with oxygen, producing heat and light.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, measured in kJ/mol.
Standard enthalpy of formation (ΔHf°)
The enthalpy change when one mole of a compound is formed from its elements in their standard states.
Enthalpy change (ΔH)
The heat content change of a system at constant pressure, measured in kJ/mol.
Standard enthalpy of formation (ΔHf°)
The enthalpy change when one mole of a compound is formed from its elements in their standard states.
Bond dissociation energy
The energy required to break a specific bond in a molecule, resulting in the formation of two radicals.
Exothermic reaction
A reaction that releases energy in the form of heat, resulting in a negative enthalpy change (ΔH < 0).