Lewis acids have been classified in the ECW model and it has been shown that there is no one order of acid strengths.
lˈuːɪs ˈæsɪdz hɐvbɪn klˈæsᵻfˌaɪd ɪnðɪ ˌiːsˌiːdˈʌbəljˌuː mˈɑːdəl ænd ɪt hˈæzbiːn ʃˈoʊn ðæt ðɛɹ ɪz nˈoʊwˈʌn ˈɔːɹdɚɹ ʌv ˈæsɪd stɹˈɛŋθs.