bond entalpy	energy needed to break 1 mol of particular covalent bond in gassous molecule in standard state
average bond entalpy	average entalpies needed to break 1 mol of particular covalent bond in gassous molecule in standard
entalpy change of reaction	energy change of reaction under standard state
exothermic reaction	energy is released
endothermic reaction	energy in absorbed
combustion, neutralization, condensing gasses, freezing liquids	exothermic reaction
energy to break bonds is less than to make bonds	exothermic
energy to break bonds is more than to make bonds	endothermic
melting ice, boiling water, dissolving	endothermic reaction
standard entalpy change of formation	energy change when 1 mol of a compound is formed from its constituing elements in the standard state
standard entalpy change of combustion	entalpy change when 1 mol of the substance burns completely under standard state