GRD Journals- Global Research and Development Journal for Engineering | Volume 5 | Issue 6 | May 2020 ISSN- 2455-5703
Spectrophotometric Determination of Available Sulphate Content in Soil Samples of Jaipur District Rashmy Nair Associate Professor Department of Chemistry S.S. Jain Subodh PG (Autonomous) College, Jaipur (Rajasthan) Chandni Jain Assistant Professor Department of Chemistry S.S. Jain Subodh PG (Autonomous) College, Jaipur (Rajasthan)
Neeru Gakkhar Assistant Professor Department of Chemistry S.S. Jain Subodh PG (Autonomous) College, Jaipur (Rajasthan)
Abstract Different soil samples were collected and determined for the concentration of sulphate content through a rapid, simple and less time-consuming spectrophotometric method. Before the estimation of the sulphate content, the sample collected was dried in air and then sieved mechanically using a 2mm mesh. The sulphate present in the different soil samples was extracted in the ratio of 1:1 using water. The sulphate anion was treated with excess barium chloride solution to produce the barium sulphate precipitate and spectrophotometric estimation of the same was carried out at 420 nm wavelength. A calibration curve was observed to be linear in the concentration range of 0.1 to 1.0 mg/l. This method is equally well utilized for determination of available sulphate in irrigation water, plant materials as well as food samples. The present paper deals with the sulphate anion present in the various soil samples collected from the Jaipur district. Keywords- Soil Samples, Sulphate, Spectrophotometry, Irrigation Water, Food Samples
I. INTRODUCTION Soil is one of the most important natural resource on earth and its chemical composition depends on the starting materials from which they are formed and it’s weathering process. Soil can also be called as a complex system that contains organic matter, inorganic matter, air, water and different organisms [1]. Plants grow on the soil and very importantly need the nutrients namely sulphur, phosphorus and nitrogen. Of these nutrients, plants need nitrogen and phosphorus the most and sulphur the least. The secondary nutrients sulphur, in the soil is absorbed by the plant roots in the form of sulphates. Sulphur deposits required by the soil are adequately met by the organic sulphur mineralization and atmosphere [2]. Depending on the type of soil, greater the amount of percolating water, greater will be the net downward movement of sulphate in the soil [3]. Bloem et al. determined that greater concentrations of sulfates are found below the first 60cm of soil [4]. The sulphate content of soil varied with season and it was found that in winter season there were maximum sulphate values whereas minimum sulphate values in rainy season[5]. The sulphates present in the soil can be determined by a number of methods. The different methods include titrimetric, gravimetric, colorimetric, turbidimetric, nephelometric and ion chromatographic methods[6,7]. Sulphate measurement in micro quantities in the soil extracts can be carried out by a sensitive method, methylene blue colorimetric determination[8] but needs analytical expertise in handling the apparatus. The ion chromatographic methods [9] are though specific for estimation of sulphates, they cost high at the initial stage. As mentioned above, the sulphates can also be determined by the spectrophotometric [10,11] and turbidimetric methods[12]. The turbidimetric method is fast and accurate but it requires a uniform solid phase of barium sulphate in the dispersing solution. Accurate results for sulphate in soil are also obtained by the Atomic absorption spectrophotometric method [11].of the various methods for estimation of sulphur in soil, the spectrophotometric method [13] is the best, accurate, more time saving and efficient method used to determine sulphur in soil and in plant materials etc.
II. MATERIALS AND METHOD A. Materials 1) NaCl-HCl Solution: Dissolve 240 g sodium chloride in minimum amount of distilled water. Add 20 ml of HCl in it and dilute with distilled water to make the volume upto 1 litre. 2) Glycerol-ethanol Solution: Dissolve 50 ml glycerol in 100ml ethanol. All rights reserved by www.grdjournals.com
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