Search results for “Enthalpy”

Energy Profile Diagram Chemical Kinetics & Catalysis kJ/mol A plot of potential energy against reaction coordinate showing reactants, transition states, intermediates and products.

Gibbs–Helmholtz Equation Thermochemistry & Thermodynamics kJ/mol The relation showing how the Gibbs free energy of a system varies with temperature. (∂(ΔG/T)/∂T)_p = −ΔH/T²

Isobaric Process Thermochemistry & Thermodynamics J A process carried out at constant pressure. q_p = ΔH

Neutralisation Reaction Stoichiometry & Chemical Reactions kJ/mol The reaction between an acid and a base to produce a salt and water. HA + BOH → BA + H₂O

Non-Ideal Solution Solutions & Colligative Properties Pa A solution that departs from Raoult's law because interactions between unlike molecules differ from those between like molecules. p ≠ x p°

Resonance Energy Chemical Bonding & Molecular Structure kJ/mol The extra stability a molecule gains from electron delocalisation, measured against the most stable single Lewis structure. ΔE_res = E(hybrid) − E(best structure)

Spontaneity Thermochemistry & Thermodynamics kJ/mol The tendency of a process to occur without any continuous external input of energy. ΔG < 0

Stoichiometric Coefficient Stoichiometry & Chemical Reactions Dimensionless The number written before a formula in a balanced equation, giving the relative amount of that substance consumed or produced.

Supersaturated Solution Solutions & Colligative Properties mol/L An unstable solution containing more dissolved solute than the equilibrium solubility at that temperature.

Transition State Theory Chemical Kinetics & Catalysis Various The theory that treats the activated complex as being in quasi-equilibrium with reactants and calculates rate from its decomposition frequency. k = (k_BT/h) e^(−ΔG‡/RT)

Van't Hoff Equation Chemical Equilibrium kJ/mol The equation describing how an equilibrium constant varies with temperature. ln(K₂/K₁) = −ΔH°/R (1/T₂ − 1/T₁)

Extensive Property Foundations of Chemistry Various A property whose value is directly proportional to the quantity of matter in the sample.

State Function Thermochemistry & Thermodynamics Various A property whose value depends only on the current state of the system, not on how that state was reached. ΔX = X_final − X_initial

Results for “Enthalpy”