Enthalpy Change Flashcards
What is the ideal gas equation?
Pressure (pa) x volume (m3) = Moles x gas constant (8.314) x temperature (K)
What is the definition of enthalpy change?
The heat transferred in a reaction at constant pressure
Why are bond enthalpies not exact?
The energy needed to break 1 mole of bonds in the gas phase is averaged over many different compounds
How can you define bond length?
The distance between two nuclei where the attractive and repulsive forces balance each other
Standard enthalpy change of reaction?
The enthalpy change when the reaction occurs in the molar quantities shown in the chemical reaction under standard conditions
Standard enthalpy change of formation?
The enthalpy change when 1 mole of compound is formed from its elements in their standard states under standard conditions
Standard enthalpy change of combustion?
The enthalpy change when 1 mole of a substance is completely burned in oxygen under standard conditions
What are the standard conditions?
298k
25 degrees
100kpa
