Atmospheric Chemistry Lab, Department of Chemistry, University of Rajasthan, Jaipur-302 004, Rajasthan, India E-mail : guptaksl4@rediffmail.com Manuscript received 06 May 2011, revised 20 March 2012, accepted 13 September 2012 The rainwater samples were collected at and around Rajasthan University Campus in Jaipur and analyzed for pH, conductance, concentration of ions, viz. bicarbonate, chloride, nitrate, sulfate, calcium, magnesium, sodium and potassium. In addition, heavy metals, viz. iron,

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... opper, lead, zinc, manganese, cobalt and nickel were also determined. The pH of rainwater lied in the range, 6.82-8.45. The ratios of the concentrations of ions relative to sodium ion concentration were determined in both rainwater and soil samples and were found to fit the eq. (A). {[X]/[Na]}rain = 0.96 + 0.95{[X]/[Na]}soil (A) The slope of nearly~1 indicates the soil to be major source of ions in water. The results of ion balance analysis between total concentrations of anions,Ʃ[An-], and total concentrations of cations,Ʃ[Mn+] were in agreement with eq. (B) showing good correlation. Ʃ[An-] =0.034 + 0.97Ʃ[Mn+] There was a good linear correlation between observed, Aobs, end calculated, Acal, conductivities in rainwater as defined by eq. (C). Acal = 0.98 + 1.02Aobs The ion balance analysis, and correlation analysis between observed and calculated conductivities were also done. Atmospheric dry deposition samples were collected from two sites and analyzed for pH, conductivity and concentrations of major ions. The deposition flux of each ion has been calculated. There was good correlation between. Ʃ[An-] and (Mn+) and between Acal and Aobs· A comparison of pH values of rainwater, dry depositions, soil and groundwater at Jaipur showed these to be generally~7 or more indicating the alkaline nature of all these.