The kinetics of the redox reaction of benzaldehyde and dichromate ions in aqueous acidic media was determined. The data obtained was carried out at wavelength,  = 420 nm, acid (H2SO4) was used to catalyze the reaction, ([H + ] = 0.1 mol dm -3 ) and temperature = 35 ± 0.5 °C. The stoichiometry of the reaction using the mole ratio method was found to be 5:1 (ArCHO:Cr2O7 2-). The rate showed first order each with respect to the reductant and oxidant and second order overall. The overall rate law was predicted as; Rate = k2[ArCHO][Cr2O7 2-], where k2 = second order rate constant for the reaction. The proposed rate equation for the reaction is:The reaction of ArCHO and Cr2O7 2was catalysed by H + through one pathway, the acid pathway. Michaelis _ Menten plot showed a positive slope with no significant intercept and the absence of intermediate complex formation suggesting a spontaneous reaction.

The fermentation of tiger nut (Cyperus esculentus var. sativus) using Saccharomyces cereviseae was carried out under varying temperature: 25oC, 30oC, 35oC, 40oC, 45oC and 50oC respectively and pH of 4.0 which changes due to temperature. The fermentation time was 8 hours for all the temperatures. The effect of temperature on the rate of fermentation of juice from tiger nut was determined using the volume of carbon dioxide produced. Fermentation rate was observed to be highest at 40oC while the pH before and after fermentation were 4.10 - 4.29 and 3.60 - 3.67 respectively. The concentrations of ethanol produced were 13.35 g/L, 27.45 g/L, 31.16 g/L, 36.35 g/L, 33.39 g/L and 28.94 g/L at 25 oC, 30oC, 35oC, 40oC, 45oC and 50oC respectively.Bangladesh J. Sci. Ind. Res. 51(2), 89-94, 2016

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The study was carried out to evaluate spatial and temporal variations in the levels of some physicochemical parameters in water and sediments from Mpape River, Abuja, Nigeria. The samples were collected along the river bank in dry and rainy seasons from five (5) locations and were analysed using standard methods. Levels of pH, nitrate, phosphate, and biochemical oxygen demand (BOD) in water did not vary according to sites. However, the highest levels of electrical conductivity (EC) and total dissolved solids (TDS) were recorded at site 4 for both seasons. During the dry season, levels of pH (7.36±0.16), EC (300.73±0.05 µs/cm), TDS (185.11±0.10 mg/L), BOD (0.98±0.30 mg/L), SO 4 2-(9.8±0.14 mg/L) and Cl-(38.00±0.15 mg/L) in water were higher. Concentrations (3.42±0.10 mg/L) of dissolved oxygen (DO), PO 4 3-(5.