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).
The standard temperature is the freezing point of water and the standard pressure is one standard atmosphere. These can be quantified as follows: Standard temperature: 0Â°C = 273.15 K Standard pressure = 1 atmosphere = 760 mmHg = 101.3 kPa Standard volume of 1 mole of an ideal gas at STP: 22.4 liters.Standard pressure = 1 atmosphere = 760 mmHg = 101.3 kPa. Standard volume of 1 mole of an ideal gas at STP: 22.4 liters.he accurate masses of pure elements with their normal isotopic concentrations can be obtained from the periodic table. One mole of an ideal gas will occupy a volume of 22.4 liters at STP (Standard Temperature and Pressure, 0Â°C and one atmosphere pressure).