Topic 4 Energetics

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Created by
Amelia Procter

Cards (8)

  • Define Enthalpy change [2]
    Enthalpy change is the heat energy transferred in a reaction at a constant pressure (kJmol-1)
  • Is breaking bonds exothermic or endothermic? Why? [2]
    You need energy to break bonds, so breaking bonds is endothermic.
  • Is making bonds exothermic or endothermic? Why?
    When a bond is made, energy is released so its exothermic
  • Define the standard Enthalpy of formation [2]
    The Enthalpy change when 1 mole of a compound is formed from elements in their standard states under standard conditions.
  • Define Enthalpy of combustion [2]
    The Enthalpy change when 1 mole of a substance is completely burned in oxygen under standard conditions
  • Define what is meant by Hess’s law [2]
    The total enthalpy change of a reaction is independent of the route taken
  • Where do the arrows point for formation of Hess’s law? [1]
    Up
  • Where do arrows point for combustion of Hess’s law? [1]

    Down