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).
Combustion Enthalpy of Combustion The reactions that produce carbon and dioxide and water from hydrocarbons in the atmosphere release the same amount of energy as the combustion of those hydrocarbons. We can measure the enthalpy of combustion by burning the hydrocarbons in a calorimeter.