ABSTRACT
The objective of the present study is to determine the nature of variation of refractive index of an aqueous solution as a function of its concentration and density. In this study, we have used aqueous solution of sodium chloride of different concentrations at the room temperature. We have constructed a novel experimental set-up for this purpose, which can be regarded as a makeshift spectrometer, using which, the angle of deviation of light by a prism can be measured with an accuracy of one degree. We have prepared sodium chloride solutions of different concentrations and put each solution in a hollow prism. The angle of minimum deviation was then measured using our setup. Refractive index has been calculated based on this angle. We also calculated the density of the solution from its concentration. The variation of refractive index as functions of percentage concentration and density has been depicted graphically. Here, the light source is a LASER pointer emitting light of wavelength 532 nm. We have devised a Python program that enables the user to get the refractive index based on inputs of the percentage concentration and density of the solution.
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