Enthalpy and Heat Changes

These flashcards cover the key concepts related to enthalpy and heat changes from the lecture notes.

Enthalpy (H)

Chemical potential energy stored in a system.

Exothermic Reaction

A process where heat flows from the system to the surroundings, resulting in a temperature increase of the surroundings.

Endothermic Reaction

A process where heat is absorbed from the surroundings into the system, resulting in a temperature decrease of the surroundings.

Specific Heat Capacity (c)

The heat needed to increase the temperature of 1 unit mass of a substance by 1 K.

Enthalpy Change (ΔH)

The change in enthalpy between reactants and products at constant pressure; positive ΔH indicates endothermic, negative ΔH indicates exothermic.

Activation Energy (Ea)

The minimum kinetic energy needed by substances to react.

Heat Change (q)

The amount of heat absorbed or released in a process, follows the unit of specific heat capacity.

Constant Pressure

The conditions under which enthalpy change (ΔH) is assessed.

Heat Transfer

The movement of thermal energy from one object to another due to a temperature difference.

Standard Conditions

The conditions of temperature (298 K), pressure (100 kPa), and concentration (1 mol.dm³) under which substances are found in their standard state.