1. 1  an implement, such as a hammer, saw, or spade, that is used by hand. 2  a power-driven instrument; machine tool. ( 3 in combination): a toolkit.
The standard enthalpy of combustion is the enthalpy change when one mole of a reactant completely burns in excess oxygen under standard thermodynamic conditions (although experimental values are usually obtained under different conditions and subsequently adjusted).he standard enthalpy of combustion is the enthalpy change when one mole of a reactant completely burns in excess oxygen under standard thermodynamic conditions (although experimental values are usually obtained under different conditions and subsequently adjusted).
1 Heats of combustion are typically stated in kilojoules per mole (kJ/mol. or kJ mol. ). 2  The accepted value for the molar heat of combustion of ethanol is 1360 kJ mol. . 3  The following steps allow the calculation of an experimental value for the molar heat of combustion of ethanol: