standard of heat combustion

Question

Define the standard heat of combustion

Answer 1

Standard enthalpy of combustion is defined as the enthalpy change when one mole of a compound is completely burnt in oxygen with all the reactants and products in their standard state under standard conditions (298K and 1 bar pressure).

Answer 2

Enthalpy change when one mole compound completely burnt in O2 with reactants in standard form under conditions 

Answer 3

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