Redox

Loss of electron is oxidation Electron gain is reduction.

$\ce a c i d + ba se - > s a lt + w a t er$ The the reaction above, the salt is ionic so no enthalpy change. The net enthalpy is very similar for all reactions between acids and bases, about -57 kJ mol-1. also

$\ce a c i d + c a r b o na t e - > s a lt + w a t er + c a r b o n d i o x i d e$ Reaction involving giving off gas is called effervescence