standard enthalpy changes

• what are standard enthalpy changes?

  those which are measured under standard conditions, eg: a pressure of 100kPa and a temperature of 298K.
• what symbol represent standard enthalpy changes?


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• what is the definition for standard enthalpy of combustion?

  the enthalpy change that occurs when 1 mole of a compound undergoes complete combustion in oxygen under standard conditions, with all substances being in their standard states.
• what is the symbol equation for standard enthalpy of combustion?


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• what must you remember when writing an equation for the standard enthalpy of COMBUSTION?

  the number of moles of the compound undergoing combustion doesn't change.
• what is the definition for standard enthalpy of formation?

  the enthalpy change that occurs when 1 mole of a compound is formed from its elements under standard conditions, with all substances being in their standard states.
• what must you remember when writing an equation for the standard enthalpy of FORMATION?

  one 1 mole of the compound being formed is used.