Ionochromism, solvatochromism and effect of dissolved gases on the spectral properties of bromothymol blue

• Bromothymol blue's spectral properties were recorded in the presence of heavy water and some selected electrolytes. The removal dissolved gases from dye solution modifies its UV–vis absorption spectrum. Re-admitted induce specific effects on features dye. color pH indicator blue (BTB) changes yellow to with increasing pH. effect electrolytes (LiCl, NaCl, KCl, CsCl, KSCN KClO 3 ) D 2 O dilute solutions BTB is explored. results are interpreted terms dimerization molecules different hydration that induces. studied. Complete gas achieved. Surprising spectra emerged. After degassing solutions, re-admitted via bubbling. He, Ar, N , CO CH 4 .were can be explained by or absence nano- microbubbles solution. These allow formation dimers multiple association adsorption so affect molecules.