Question

Discuss the various analytical Methods for the analysis of “Sulfur dioxide in air”and give your critical thoughts on these methods?

4 pages only ?

Answer 1

Determination of so, in air by ion I chromatography i) The sample of so, was collected in a dilute solution of H₂O with the help of a Anderson Sampler, and analysed by ion chromatography ( The detection limit for sulphate was 0.044 ugime, based on three times the Standard deviation of the blank (n=23) · 18 For a sulfate sample with a mean of 0.198 uglme "(n=7), á relative standard deviation of 5.569). was obtained (W) The The recovery recovery of of a a sulfo sulfate standard (02 g/ml) was 99.6. . (V) During Dey season, most of the so, Concentration were delected by H2O2 ion chromatography:

2 air û So, in method determined by colorimetric photo detection a reeferenced i) so we's analysed using a Droplet Colleetor of Malachite creen Soluliou. ii)Opposite side of a green malachite Holution, - two optical fibres is placed. i) when the night is passed through the droplet , the light which is transmitted oli measweed by a referenced photo arrangement - The source of light is monochromatic at . Amax = 625 um (²) The SO2 is collected by the droplet, and recacts with malachite green and o Shows a colourless dye. . (V) This colorless of the solution is proportional to so, concentration :

cui i determined by conductometra 3). So in ... method. j) So, e analysed by conductometric method using Its reaction with a dilute hydrogen peronide solution, where H₂ soy acid produced increases the conducivity of the solution. 3) Some instruments can be used for the Conductometric determination of water vapour on the basis of its reaction with 94-99% H₂SO4 . 1) Conductometric analysis measures the increase in conductivity as soz is absorbed into a H₂O solution .

4). Soz dekecked by using Fluorescence i). So, molecule absorb ligué at a specific - wavelength (214 nm) and emit light at a longer wavelength 1: Fluorescence occur as the molecules emit excess energy and return to ground state dit) The distribution of wavelength is dependent on intensity of emitted energy I