ABSTRACT. Physico-chemical properties and heavy metals content of soils were determined from seven farms in Minna, central Nigeria. Conventional analytical methods were employed to determine the physico-chemical properties and the heavy metals were analysed by atomic absorption spectrometry. The result showed that pH values ranged from 6.64 -7.70 indicating slight acidity to slight alkalinity of the soils. The total organic carbon values ranged from 0.95-2.25 % resulting in the presence of organic matter (1.63-3.87). The electrical conductivity values ranged from 17-37 µS/cm. The cation exchange capacity of the soil samples ranged from 3.68-5.15 cmol/kg. The heavy metals levels were in the following range: Cd (0.00018-0.00134 mg/g), Cu

Kinetic and mechanistic studies of electron transfer reaction of butane-1,3-diol and Cr(VI) ion in aqueous acidic medium have been carried out in aqueous medium at 27±1°C, I = 1.0 mol dm -3 (NaCl), [H + ] = 0.5mol dm -3 (HCl). The reaction was inhibited by added anions and showed negative salt effect. Spectroscopic investigations confirmed that precursor complex formation did not precede the electron transfer step. Interpretation of these observations suggest that the reactions most likely occur by the outersphere mechanism .

Oxidative properties of Cr(VI) are of considerable importance in both analysis and oxidation of organic and inorganic substrates 1,2,3. Cr (VI) in water exists as CrO 4 2-, HCr 2 O 7 2and H 2 Cr 2 O 7 2,4. Of all these species, HCrO 4 has been identified as the only active oxidizing species in aqueous acidic solution 1,2,5,6,7. Although some kinetic information has been published on the oxidation of secondary alcohol by Cr(VI) 1,2, 8-16 complementary studies on its possible reaction pathways are scanty. It is in the light of this that the present work was undertaken with the aim of providing relevant information on the plausible mechanism for the electron transfer reaction of 2-methylpentane-2,4-diol. EXPERIMENTAL Materials 2-methylpentane-2,4-diol (BDH) hereafter referred to as diol was used as supplied in making its standard solution. Sodium dichromate solution in distilled water was then standardized using titrimetric method 17. A stock solution of HCl was prepared by diluting the commercial acid (M&B) and the solution was standardized titrimetrically using sodium carbonate. Stock solutions of sodium methanoate, sodium chloride and sodium ethanoate were prepared from Analar grade salts.

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The seasonal variations in the concentrations of Cd, Cr, Cu, Ni and Pb in the soils and Abelmochus esculentus fruit grown near 5 dumpsites in Kafanchan metropolis, Nigeria were investigated during the wet and dry seasons of 2015 using atomic absorption spectrophotometry. The soils were sandy loam and alkaline, with the cation exchange capacity, soil particle size distribution, pH, nitrogen, phosphorus and organic matter being higher in the dry season than in the wet. In the dry season,