This paper aims at studying the influence of acid and alkali solutions on the swell behavior of a non-expansive soil. Sulphuric acid (acidic medium); sodium hydroxide (alkaline medium) of 1 N and 4 N concentrations were used as pore fluids to understand the influence of acid and alkali pore fluids on the swell behavior of kaolin clay relying on one-dimensional free swell tests. Results showed that kaolin clay exhibits maximum equilibrium swelling of about 41% in acidic medium and 22% when interacted with alkaline medium. It is further observed that the magnitude of induced swell in clays is dependent on dispersion of clay particles leading to the formation of new minerals under both acidic and alkaline media. In order to better understand the mechanism responsible, the contaminated soil was investigated for changes in mineralogy and microstructure relying on x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) at the end of interaction. The formation of zeolite minerals viz. sodalite in alkaline media and aluminum sulphate hydrate hydroxide in acidic media were noted from XRD results. Furthermore, SEM studies revealed rosette-type morphological structure(s) in case of 4N NaOH and needle-like structures in H₂SO₄.