Module 3 : Teacher 2 Flashcards
What is first ionisation energy?
The energy needed to remove one mole of electrons from one mole gaseous atoms.
What is second ionisation energy?
The energy needed to remove on mole from each 1+ ion in one mole gaseous 1+ ions.
What is enthalpy change?
The energy change (KJ) when one mole of gaseous atoms each lose an electron to become one mole of gaseous 1+ ions.
What is enthalpy change of formation?
When 1mole of a compound is formed from its elements under standard state conditions
What are the standard state conditions
?
298 K or (25C)
100KPA or (1atm)
What is enthalpy change of combustion?
When 1 mole of a substance is fully reacted with oxygen ( complete combustion) at standard state conditions.
What is enthalpy change of neutralisation?
When per mole of water formed when acid and base react under standard conditions.
What is average bond enthalpy?
The average energy needed to break 1 mole of a covalent bond in a gaseous state.
What type of energy does breaking bonds require?
endothermic input energy
What type of energy does making bonds require?
exothermic input of energy
What is Hess’s law?
The enthalpy change for a chemical reaction is independant of the route taken provided the start and end point are the same.
