ðɛɹ ɪz ɐ tɹˈɛnd ʌv ɪŋkɹˈiːsɪŋ ɡˈæsfˈeɪz æsˈɪdᵻɾi ænd kˌɔːɹɪspˈɑːndɪŋ pˈiː kˈɑː æz ðə nˈʌmbɚɹ ʌv ˈɑːksɪdʒən ˈæɾəmz ɪnðə tʃˈeɪn ˈɪŋkɹiːsᵻz ɪn ˈeɪtʃ ˌɔn ˈeɪtʃ stɹˈʌktʃɚz ˈɛn ˈiːkwəlz wˈʌn,tˈuː,θɹˈiː.
There is a trend of increasing gas-phase acidity and corresponding pKa as the number of oxygen atoms in the chain increases in HOnH structures (n=1,2,3).