"the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur; \"catalysts are said to reduce the energy of activation during the transition phase of a reaction\""@en-us . "0"^^ . . . . . "0"^^ . "activation energy"^^ . . . "111421822"^^ . "energy of activation"@en-us . . "activation energy"@en-us . . . . "11421822-n"^^ . "110683393"@en-us . . "107772907"@en-us .