Topic 6 energy definitions Flashcards
(14 cards)
What is the standard enthalpy of vaporisation?
The energy required to vaporise one mole of a liquid.
This enthalpy value is important in thermodynamic calculations involving phase changes.
Define enthalpy of atomisation.
The energy required to produce one mole of gaseous atoms from an element in its standard state.
This process is essential for understanding bond energies and reactions.
What is bond dissociation enthalpy?
The energy change when one mole of a specific bond is broken or created under standard conditions.
This value varies depending on the type of bond and the surrounding environment.
What does standard bond enthalpy refer to?
The average energy change when one mole of covalent bonds is broken or created under standard conditions.
It provides a measure of bond strength in a molecule.
What is the enthalpy of combustion?
The energy released when one mole of a compound is burned in excess oxygen completely.
This value is crucial for understanding energy content in fuels.
Define standard enthalpy of formation.
The energy change when one mole of a compound is formed from its constituent elements in their standard states under standard conditions.
This is a fundamental concept for calculating reaction enthalpies.
What is the standard enthalpy of solution?
The energy change when one mole of a substance is dissolved in an infinite amount of water under standard conditions.
It helps in understanding solubility and solution formation.
What does standard dehydration enthalpy represent?
The energy change when a particle is taken from infinite separation in the gaseous state to its position in an aqueous lattice.
This enthalpy is important in hydration and solvation processes.
Define ionisation energy.
The energy required to remove one mole of electrons from one mole of gaseous atoms in the ground state to produce one mole of gaseous ions.
This property is critical for understanding chemical reactivity and periodic trends.
What is lattice enthalpy?
The energy change when one mole of an ionic substance is broken into its constituent ions at infinite separation.
This value indicates the strength of ionic bonds in a compound.
Define enthalpy of hydration.
The energy change when 1 mole of gaseous ions are dissolved in water to create a solution of infinite dilution.
This enthalpy is essential for understanding the interactions between ions and water.
What is the enthalpy of solution?
The energy change when 1 mole of a solid crystalline/ionic substance dissolves in water to give a solution of infinite dilution.
It reflects the energy dynamics involved in dissolving solids.
True or False: Bond formation is endothermic.
False.
Bond formation is an exothermic process, resulting in a negative ΔH.
True or False: Bond cleavage is exothermic.
False.
Bond cleavage is an endothermic process, resulting in a positive ΔH.
