Home Wikituition Browse all terms Categories
Random term

Thermochemistry & Thermodynamics

13 terms

A–Z
All A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Filtering by: Thermochemistry & Thermodynamics Starts with E Clear all
Thermochemistry & Thermodynamics

Endergonic Reaction

A reaction with a positive Gibbs free energy change, which requires an input of energy to proceed.

ΔG > 0 kJ/mol Thermochemistry & Thermodynamics

Enthalpy

A thermodynamic state function equal to internal energy plus the product of pressure and volume.

H = U + pV kJ/mol Thermochemistry & Thermodynamics

Enthalpy Level Diagram

A diagram plotting the enthalpies of reactants and products to show the direction and size of the enthalpy change.

kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Atomisation

The enthalpy change when one mole of gaseous atoms is produced from an element in its standard state.

ΔH_at° kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Dilution

The enthalpy change when a solution is diluted from one concentration to another by adding solvent.

ΔH_dil kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Fusion

The enthalpy change when one mole of a solid melts to a liquid at its melting point.

ΔH_fus kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Neutralisation

The enthalpy change when an acid and a base react to form one mole of water under standard conditions.

H⁺ + OH⁻ → H₂O, ΔH = −57.1 kJ kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Reaction

The heat absorbed or released when a reaction occurs at constant pressure in the molar amounts of the balanced equation.

ΔH_rxn = ΣΔH_f(products) − ΣΔH_f(reactants) kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Sublimation

The enthalpy change when one mole of a solid converts directly into vapour.

ΔH_sub = ΔH_fus + ΔH_vap kJ/mol Thermochemistry & Thermodynamics

Enthalpy of Vaporisation

The enthalpy change when one mole of a liquid becomes vapour at its boiling point.

ΔH_vap kJ/mol Thermochemistry & Thermodynamics

Entropy

A measure of the dispersal of energy and the number of microscopic arrangements available to a system.

S = k ln W J/(mol·K) Thermochemistry & Thermodynamics

Entropy Change of the Surroundings

The entropy change experienced by the surroundings when they absorb or release heat from a system.

ΔS_surr = −ΔH_sys / T J/K Thermochemistry & Thermodynamics

Exergonic Reaction

A reaction with a negative Gibbs free energy change, which therefore releases usable energy and proceeds spontaneously.

ΔG < 0 kJ/mol