EXPERIMENTAL DETAILS

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Austin Rogers
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1 EXPERIMENTAL DETAILS

2 2.1 Preparation Of Solutions:- For the present work all the the solvents, Reagent and chemicals used were of Sdfine / Riedel Make. The purity of the chemicals and reagents were extra pure quality of AnalR grade and these were used as received without any further treatment. All the solutions and the reagents required during the course of study were prepared and standardized using suitable methods as described in literature, 61, For these preparations doubly distilled water is used except otherwise stated Preparation of NaOH 4 N NaOH is prepared by dissolving 160 gm in 1000 ml of distilled water. Solutions of different concentrations such as 1N, 0.1N, and 0.01 N are prepared using this stock solution. 1 N and 0.1N solution are prepared by diluting 125 and 12.5 ml stock solution to 500 ml respectively while 0.01 N is obtained by diluting 50 ml of 0.1 N NaOH to 500 ml with distilled water. Further it is standardized using method available in literature Preparation of HCl solution 4 N HCl is prepared by diluting 348 ml of conc HCl (Specific gravity 1.18 and Percentage by weight 35% Normality 11.3N) in 1000 ml of distilled water. Solutions of different concentrations such as 1N and 0.1N are prepared using this stock solution. 1 N and 0.1N solution are prepared by diluting 125 and 12.5 ml stock solution to 500 ml

3 respectively while 0.01 N is obtained by diluting 50 ml of 0.1 N HCl to 500 ml with distilled water. All the diluted solutions are standardized volumetrically Preparation of acetic acid solution 4 N CH 3 COOH is prepared by diluting 232 ml of glacial acetic acid (Specific gravity 1.05 and Percentage by weight 99.5% Normality 17.4N) in 1000 ml of distilled water. Solutions of different concentrations such as 1N and 0.1N are prepared using this stock solution. 1 N and 0.1N solution are prepared by diluting 125 and 12.5 ml stock solution to 500 ml respectively while 0.01 N is obtained by diluting 50 ml of 0.1 N CH 3 COOH to 500 ml with distilled water. The solutions prepared were standardized using standard sodium carbonate solution Preparation of ammonia solution 4 N NH 3 is prepared by Diluting 348mL of conc NH 3 (Specific gravity 0.91 and Normality 14.3 N) in 1000 ml of distilled water. Solutions of different concentrations such as 1N and 0.1N are prepared using this stock solution. 1 N and 0.1N solution are prepared by diluting 125 and 12.5 ml stock solution to 500 ml respectively while 0.01 N is obtained by diluting 50 ml of 0.1 N NH 3 to 500 ml with distilled water. The solutions were standardized using standard oxalic acid solution

4 2.1.5 Preparation of 2N Oxalic acid solution. 63 gm oxalic acid is dissolved in 500 ml distilled water to get 2N Preparation of Indicator Solution 500 mg of separated samples are dissolved in 50 ml of alcohol. Similarly phenolphthalein and methyl orange indicator solutions are obtained by dissolving 500 mg in 50 ml alcohol Calcium Chloride Solution 0.1 M calcium chloride solution is prepared by dissolving gm in 100 ml of distilled water Zinc Chloride Solution 0.1M zinc chloride solution is obtained by dissolving gm in 100 ml distilled water Magnesium Chloride Solution It is prepared by dissolving gm Magnesium Chloride in 100 ml of distilled water. The resultant solution is 0.1M Cobalt Nitrate Solution It is prepared by dissolving gm Cobalt Nitrate in 100 ml of distilled water. The solution is 0.1M

5 Cadmium Nitrate Solution It is prepared by dissolving gm Cadmium Nitrate in 100 ml of distilled water. The resultant solution is 0.1M EDTA Solution It is prepared by dissolving gm EDTA di sodium salt in 1000 ml of distilled water. The concentration of the resultant solution is 0.1M Buffer Solutions Buffer solution of 2.0 ph to 11.0 ph were prepared as per standard procedure 63, 64 and their exact ph is measured with ph meter. 2.2 Glassware ph meter and their calibration. For the present investigation, the glassware such as pipette, burette, volumetric flask and specific gravity bottles used were of Borosil make Calibration of glassware Burette, pipette and volumetric flask of capacities 50 ml, 100mL, 250mL, 500mL, were calibrated before using by weight method as described in literature

6 2.2.2 Calibration of ph meter ph meter was of Elico India made model LI 120 used for the experiments A combined electrode (Calomel and glass electrode) attached to it. Saturated KCl was filled and electrode is kept in 0.1N HCl solution for 24 Hours before using it. ph meter is calibrated with the help of 4 ph buffer solution and 9.2 ph. Buffer solutions were prepared by dissolving the tablets provided by Elico company in 100 ml of distilled water. The accuracy of the instrument was ` Spectral determinations UV-visible spectrophotometer used for the recent work is Elico India made (Model SL 159) which has a range between 200 to 1000 nm. Samples were scanned for the spectra by selecting wavelength range 200 to 800 nm. I R spectra of the samples are recorded in Nujol oil. NMR spectra of the samples were taken in DMSO and with internal reference on 300 MHz instrument. Mass spectra are recorded on the instrument Model No. 2.4 Flower samples Sample A It is collected from Ajanta Hills in the month of February 2004, identified as Erythrina variegata by Dr Rafiuddin Naser Lecturer Aurangabad college for women, Navkhanda, Aurangabad and sample signatured is kept with him. Petals of these flowers were separated and

7 dried in dark i.e. in absence of direct sunlight. Grinded to powder about 2 Kg in quantity Sample B It is collected from Harsool area in the month of February 2004 identified as Erythrina superba by Dr, Rafiuddin Naser Lecturer Aurangabad college for women, Navkhanda, Aurangabad and sample signatured is kept with him. Petals of these flowers were separated and dried in dark i.e. in absence of direct sunlight. Grinded to powder about 2 Kg Sample C It is collected from Phulambri, at 25 km in the north of Aurangabad in the month of February 2004 identified as Bombex Ceiba L by Dr Rafiuddin Naser Lecturer Aurangabad college for women, Navkhanda, Aurangabad and sample signatured is kept with him. Petals of these flowers were separated and dried in dark i.e. in absence of direct sunlight. 2 Kg of sample Grinded to powder Sample D It is collected from nearby area of Harsool Dam, Aurangabad in the month of June 2004 identified as Russelia equisetiformis Schlecht. by Dr Rafiuddin Naser Lecturer Aurangabad college for women, Navkhanda, Aurangabad and sample signature is kept with him. Petals

8 of these flowers were separated and dried in dark i.e. in absence of direct sunlight. Grinded to powder about 2 Kg obtained. 2.5 Extraction procedure. 100 gm of powder is extracted using soxhlet apparatus 66 by heating with ethanol for 72 Hours on water bath. The extraction procedure was repeated 5 times. Extract is collected and alcohol is distilled. A dark brown semisolid mass is obtained thus checked for different compounds such as alkaloids, protein, carbohydrate, tannins etc 67, 68. by chemical tests. 2.6 Separation of components Semi solid extract then tested for TLC 69, 70 using n-hexane, ethylacetate, chloroform, 2-butanone, in different combinations. Fractions are separated with the help of column. A Column (3.5 cm in diameter and 25 cm in height) is prepared using slurry of 100 gm silica gel (Mesh ) in n-hexane. 1.5 gm of sample is loaded in the column and extracted with first 100 ml of n-hexane followed by 100 ml of 2% ethylacetate in n-hexane and percentage of ethyl acetate increased by 2% to 4%, 6%,8%,10%, 12%,14%,16%,18% 20% etc. Different fractions are collected and checked for its purity by TLC. Procedure repeated 4-5 times. Fraction which show change in colour in acid and alkaline medium are collected and used for further studies

9 Sample A is eluted in 12% EtOAc in hexane Sample B is eluted in 8% EtOAc in hexane Sample C is eluted in 10% EtOAc in hexane Sample D is eluted in 26% EtOAc in hexane Solvent are evaporated by distillation under vacuum to get solid. 2.7 Titrations 10mL acid solution is pipetted out and transferred to 100 ml beaker. Then added 40 ml distilled water and 1mL indicator / Sample solution. Combined electrode is dipped and ph meter connected. The solution in the beaker is titrated against alkali/base solution. ph of the solution is noted after the addition of 0.5/0.2/0.1 ml solution from burette using traditional in acid base indicator as well as samples under investigation as novel indicator Acid Base titrations out using The following set of combinations of acid and base are carried 4 N HCl Vs 4 N NaOH 4 N HCl Vs 4 N NH 3 4 N CH 3 COOH Vs 4 N NaOH 4 N CH 3 COOH Vs 4 N NH 3 1 N HCl Vs 1 N NaOH

10 1 N HCl Vs 1 N NH 3 1 N CH 3 COOH Vs 1 N NaOH 1 N CH 3 COOH Vs 1 N NH N HCl Vs 0.1 N NaOH 0.1 N HCl Vs 0.1 N NH N CH 3 COOH Vs 0.1 N NaOH 0.1 N CH 3 COOH Vs 0.1 N NH N HCl Vs 0.01 N NaOH 0.01 N HCl Vs 0.01 N NH N CH 3 COOH Vs 0.01 N NaOH 0.01 N CH 3 COOH Vs 0.01 N NH 3 Every set of titration is carried out using each sample under investigation as indicator, phenolphthalein and methyl orange separately Reverse titrations The titrations are carried out by taking acid in burette and base in beaker with sample/ indicator solution Complexometric titrations 0.1 M solutions of Cd 2+, Ca 2+, Mg 2+, Zn 2+ and Co 2+ ion are titrated with 0.1 M EDTA solution in presence of buffer solution. Following complexometric titrations were carried out

11 0.1 M EDTA Vs 0.1M Ca M EDTA Vs 0.1M Mg M EDTA Vs 0.1M Cd M EDTA Vs 0.1M Co M EDTA Vs 0.1M Zn M EDTA Vs 0.1M Cu

ANALYTICAL TASK EXPERIMENTAL PROCEDURE

ANALYTICAL TASK EXPERIMENTAL PROCEDURE Complexometric determination of zinc after separation from cadmium by ion chromatography It is almost impossible to correctly determine the content of zinc(ii) ions