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).
(a) Calculate the standard enthalpy change for the combustion of 1 mol of benzene, C 6 H 6 (l), to CO 2 (g) and H 2 O (l). (b) Compare the quantity of heat produced by combustion of 1.00 g propane to that produced by 1.00 g benzene. SOLUTION (a) We know that a combustion reaction involves O 2 (g) as a reactant.