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EXPERIMENTS INANALYTICAL CHEMISTRYA.V.R. ReddyK.K. SwainK. VenkateshASSOCIATION OF ENVIRONMENTALANALYTICAL CHEMISTRY OF INDIA

Printed by Mr. Vilas SangurdekaratPerfect Prints22/23, Jyoti Industrial EstateNooribaba Darga RoadThane 400 601, INDIATel. 022-2534 1291Copyright 2012byASSOCIATION OF ENVIRONMENTALANALYTICAL CHEMISTRY OF INDIAFor copies and other information, please write to:Secretary,Association of Environmental Analytical Chemistry of IndiaC/o Analytical Chemistry DivisionBhabha Atomic Research CentreTrombay, Mumbai 400 085INDIAFAX : 91 22 25505151

Association of Environmental Analytical Chemistry ofIndia (AEACI)Association of Environmental Analytical Chemistry of India (AEACI ) wasfounded on 30th November, 2010 during a meeting held at Analytical ChemistryDivision (ACD) in Bhabha Atomic Research Centre (BARC), Trombay, Mumbai toprovide a common platform to all the Indian scientists and scholars working in thefield of Analytical & Environmental Chemistry within the country from variousUniversities or Institutes or Industries. AEACI is a non-profit-making organizationwith its Head-Quarters at Analytical Chemistry Division, BARC, Mumbai. AEACIaims to promote the analytical environmental sciences and technology in India, todisseminate scientific and technological knowledge within the country and toadvance both national and international cooperation (in particular south Asianscountries) in the area of analytical and environmental Chemistry. The motivationto commence a national forum like AEACI came from the discussion in theSchool of Analytical Chemistry held at BARC, Mumbai during November 19th to26th November in 2011. Since its inception, the Association has evolvedmagnificently to represent a truly National Organization and at present, itcomprises about 155 life-members from different parts of India. The Executivecommittee of AEACI , which manages all the activities of AEACI, is being electedtriennially by the members of AEACI. The scientific and technological foraprovided by AEACI comprise the following. Symposia – that address environmental issues in a broad sense, butalways include analytical environmental chemistry as a central topicWorkshops – that are dedicated to specific topical areas of analyticalenvironmental researchShort courses – that are intended to familiarize scientists or engineerswith new techniques applicable in carrying our environmentally relevantinvestigations.To provide partial financial assistance to Indian Scientist (AEACI,members) to South Asian Countries.AEACI plans to have biannual Bulletins with guest editors from differentfields in the area of analytical environmental chemistry.To encourage scientists & technologists AEACI will institute a few awards torecognize and honour valuable contributions of Indian Scientists or scholars inthe area of analytical environmental Chemistry. Please visit the “Awards” sectionin the AEACI website (www.aeaci.org) to know details about these awards and tonominate for awards.R.K. SinghalGeneral Secretary, AEACI

About School on Analytical ChemistryAnalytical chemistry an interdisciplinary science and often is called centralscience that contributes to every branch of science. Analytical chemistry findsapplication in all the branches of science like chemistry, physics, biology, geology,materials science, nuclear science and technology, medicine, environment and industry.Analytical measurements are aimed at obtaining qualitative and quantitative informationabout the composition and structure of various materials that have relevance to bothfundamental understanding as well as applications towards improving the quality of life.Obtaining precise and reliable data is the prime requirement in the studies involvingmedical products, clinical evaluations, Environment impact and remediation, and hightech products. These data may be used in decision making. In view of this, a host ofinstrumental methods have been developed. The pace of development compares withthat of electronics industry. It is also essential to evaluate essence of the problem andchoose the right method that is fit for the purpose. Therefore analytical scientists need agood working knowledge of the available techniques, awareness about theadvancements made in instrumentation and methodologies, and have to adapt“continued education” approach for keeping abreast with the advancements intheoretical and experimental knowledge associated with the state-of-the-art analyticalmethodologies. One of the major requirements is understanding the underlying principleof the chosen method for a particular analysis. During the last century with the advent ofelectronics, rapid improvements in computer technology and automation of instrumentalmethods of analysis, a large number of instrumental methods are made available toanalytical chemists. Veracity of analytical data not only depends on choosing the correctinstrumental method, materials, procedures and evaluating the measured results intoconcentrations of the analytes but more on understanding the phenomenon of signalgeneration and deciphering reliably signal from background.It was thought that this could be achieved through organizing a 7 day School ofAnalytical Chemistry with an objective of providing a forum for revisiting fundamentals ofanalytical chemistry and exchanging with experts, the latest developments in analyticalchemistry and its applications. In addition to regular lectures on various aspects ofanalytical chemistry, laboratory experiments were included in this School to providehands on experience to the participants. It is expected that the participants will takeadvantage of the presence of experts and interact with them in a manner that facilitatescollective growth in the field of analytical chemistry. While formulating the syllabus forthe first school, some topics to impart the essence of work-culture, safe practices andgood laboratory practices, besides theoretical and experimental aspects were included.I am very happy that Analytical Chemistry Division has taken lead in organizingthis School in a Works-shop mode. It was planned for 50-60 participants, mainlycomprising of research scholars, young academics and young scientists from researchinstitutions like BARC, with Chemistry and Physics background. An examination isincluded on the last day of the Second School and the performance of the participantswas very good. Feedback from the first School encouraged us to make this School aregular feature and for the first time, the third School will be organized in a university (S.K. University, Ananatapur) during February 24 - March 01, 2012. It is heartening thata fledgling Association, AEACI has come forward to extend cooperation to organize thisSchool and thanks are due to all the members of EC, AEACI, particularly Dr. T.

Mukherjee, President, AEACI and director, Chemistry Group for all the support andguidance provided. Dr. R. Sinha, Director, BARC has been a source of inspiration in allour endeavours and his patronage to this School is gratefully acknowledged.Dr. S. Banerjee, Chairman, Atomic Energy Commission and Secretary, Department ofAtomic Energy for his continued guidance and encouragement.Organising such a School is not possible without the generous funds from theBoard of Research in Nuclear Sciences (BRNS). I take this opportunity to thank Prof. P.Rama Rao, Chairman, BRNS, Shri S.G. Markandeya, Scientific Secretary, BRNS,Members of the Board and Dr. S. Kailas, Chairman, Basic Sciences Committee, BRNSfor their support. I thank the cooperation extended by all the members of AnalyticalChemistry Division and administrative colleagues.A.V.R. ReddyHead, Analytical Chemistry Division

Presidential MessageGreetings to each one of you from AEACI and from all the members of ManagingCommittee of AEACI. Hope that all of you have also received the hard copy of thepamphlet for the School on Analytical Chemistry to be held at S.K. University,Anantapur, during February 24 - March 01, 2012. If not, please download the same fromthe website http://www.aeaci.org . This School consists of lectures in the morningsessions and laboratory experiments in the evening sessions. The target participants willbe young academics, research scholars, industrial personnel and budding scientistsfrom research centres. A total of 50 applicants will be selected as participants for thisSchool on all India basis. I am glad that my colleagues made efforts to publish a book on‘Experiments in Analytical Chemistry’ which will serve as a laboratory manual not only inSAC 2012 but also to M.Sc. students in Analytical Chemistry.Delegates and colleagues from India and overseas working in the area ofenvironmental and analytical chemistry are welcome to join hands with us, by becominglife-members of AEACI, to promote the growth of environmental and analytical chemistryworld-wide. We propose to work synergistically with other Societies in India and abroad,working in the field of environmental and analytical chemistry, to make use of themultifaceted applications of environmental analytical chemistry for the benefit ofmankind. Let us all work together to take the discipline of Environmental and AnalyticalChemistry to newer heights and make India as one of the internationally known leadersin this branch of science.My best wishes to each one of you in this challenging endeavour and lookforward to discuss at length scientifically during the upcoming events.You are welcome to suggest the names of reputed scientists and academiciansfrom India and abroad in this field who can deliver lucid and inspiring lectures in theupcoming events as well as in the continuous educational programmes of AEACI.Dr. T. MukherjeeDistinguished ScientistDirector, Chemistry GroupBhabha Atomic Research CentreTrombay, Mumbai 400 085

PrefaceAnalytical Chemistry is useful in all the branches of science like chemistry,physics, biology, geology, materials science, nuclear science and technology, medicine,environment and industry. Analytical measurements are aimed at obtaining qualitativeand quantitative information about the composition and structure of various materialsthat have relevance to both fundamental understanding as well as applications towardsimproving the quality of life. Analytical scientists need a good working knowledge of theavailable techniques, awareness about the advancements made in instrumentation andmethodologies. In view of this Analytical Chemistry Division, BARC has initiated toorganize a series of School on Analytical Chemistry for the benefit of young scientists,academics and research scholars with chemistry background and those who usechemical instrumentation of analysis in their work. In this School lectures are planned inthe morning hours, laboratory experiments in the afternoon hours to provide hands onexperience to the participants and specialized plenary lectures in the evening hours toprovide an insight into the frontiers of Analytical Chemistry. Although many good textbooks in the subject analytical chemistry are available, there is a paucity of books onexperiments in Analytical Chemistry. This book on experiments in Analytical Chemistryis an effort to provide a simple introduction to about 25 experiments covering variousaspects of instrumental methods of analysis. A few of the experiments are chosen ineach school and therefore this book is written as a manual with a provision to note theobservations and perform calculations. In addition a brief introduction is provided on afew relevant topics to inculcate laboratory work-culture, safe practices in the laboratoryand good laboratory practices, besides theoretical and experimental aspects. This bookis modeled on an IANCAS publication of Experiments in Radiochemistry: Theory andpractice.We thank all the authors who contributed to various experiments. We also thankother colleagues who have gone through the book critically.Association ofEnvironmental Analytical Chemistry of India (AEACI) has come forward to publish thisbook and we record our gratitude to the members of executive committee, AEACI led byDr. T. Mukherjee, President, AEACI and Director, Chemistry Group. Dr. R. Sinha,Director, BARC has been a source of inspiration in all our endeavors and his patronageto this School is gratefully acknowledged. We record our gratitude to Dr. S. Banerjee,Chairman, Atomic Energy Commission and Secretary, Department of Atomic Energy forhis continued guidance and encouragement. We thank Prof. P. Rama Rao, Chairman,Board of Research in Nuclear Sciences (BRNS) for his encouragement and support.This book is composed meticulously by Shri Sharad Nalavade and Shri Vishal N.Koli and we thank them for their whole hearted efforts. Our office colleagues SmtVaishali Wade and Smt S D. Shinde deserve appreciation for their cooperation andcontribution.A.V.R. ReddyK.K SwainK. VenkateshAnalytical Chemistry DivisionFebruary 18, 2012

Table of ContentsAssociation of Environmental Analytical Chemistry of India (AEACI)About School on Analytical Chemistry Presidential MessagePresidential MessagePrefaceChapter 1General Analytical Chemistry.1Basic Tools in Analytical Chemistry .4Safety Practices in a Chemical Laboratory . 6Sampling and Sample Preparation .9Analysis Methods .12Instrumental Methods of Analysis.13Basic Function of Instrumentation .16Signal generation, blank corrections, Calibration and Standardisation .17Treatment of Analytical Data . 19Some Aspects of Quality in Analytical Chemistry. 22LABORATORY EXPERIMENTSChapter 2ANALYTICAL SPECTROSCOPY .29Experiment 1Spectrophotometric Determination of Fe in WaterSample using Standard Addition Method .30Experiment 2Determination of Complex Ion Composition byJob’s Method of Continuous Variation .32Experiment 3Determination of Fe in Copper Metal by FlameAtomic Absorption Spectrometry (FAAS) .34Experiment 4Determination of Trace Metals (Fe, Ni, Cu, Cr andZn) in Environment Water Samples by FlameAtomic Absorption Spectrometry (FAAS) .36Experiment 5Determination of Cadmium (Cd) in BiologicalReference Material using Graphite Furnace Atomic

Experiment 6Absorption Spectrometry (GFAAS).39Determination of Arsenic in Ground Water usingHigh Resolution Continuum Source HydrideGeneration Atomic Absorption Spectrometry (HG-AAS) .41Experiment 7Determination of Cu, Ni and Zn in soil by ICP-OES.43Experiment 8Determination of Uranium in Ground Water by ICP- MS.45Chapter 3Chromatographic Methods.47Experiment 9Determination of Pesticides (Organophosphate) in SoilSample using HPLC .48Experiment 10Determination of Anions in Aqueous Samples usingIon Chromatography .50Experiment 11Determination of Hydrogen in the Gaseous Sampleusing Gas Chromatography .52Experiment 12Determination of Hydrocarbons in a Sample by GasChromatography (GC) .53Experiment 13Determination of Organics in Ground Water using GasChromatography / Mass Spectrometry .55Chapter 4Nuclear Analytical Techniques .57Experiment 14Determination of Absolute Activity by High ResolutionGamma ray Spectrometry using High PurityGermanium (HPGe) Detector .59Experiment 15Determination of Radioactivity in Surface Soil, Cementand Fly Ash .62Experiment 16Determination of Manganese in Steel by NeutronActivation Analysis .64Experiment 17Multielement Determination in Soil by SingleComparator NAA .66Experiment 18Determination of Thickness of Films by RutherfordBackscattering Spectrometry (RBS) .67Chapter 5Thermal And Electrochemical Methods Of Analysis .69Experiment 19Determination of ΔHmelting of Indium using DTA Technique .71

Experiment 20TG and DTA Techniques to Study of ReactionMechanism of Potassium Tetraoxalate atElevated Temperatures .72Experiment 21Determination of the Solubility ProductConstant of AgCl .73Experiment 22Determination of Toxic Elements by ElectrochemicalMethod .76Experiment 23Determination of Cu, Pb and Cd in Water Sampleby Differential Pulse Anodic StrippingVoltammetry (DPASV) .79Chapter 6Environmental Analytical Chemistry .81Experiment 24Estimation of Ammonia in Water using Kjeldahl Method .81Experiment 25Estimation of Mass Concentration of Aerosols .83Experiment 26Effect of Synoptic Meteorology on Aerosols .85Experiment 27Analysis of BOD and DO in Waste Water Sample .88Experiment 28Determination of Chemical Oxygen Demand (COD) .91Experiment 29Analysis of Fluoride in Ground Water and Potable Water .93Annex IFundamental Constants .95Annex IIConversion factors .96

1Experiments in Analytical ChemistryChapter 1GENERAL ANALYTICAL CHEMISTRYA.V.R. Reddy, K. Venkatesh, Sanjukta A. Kumar, K.K. Swain and R. VermaINTRODUCTION0BAnalytical Chemistry is the science of measurement based on a set of ideas andmethods employing state-of-the-art technology. Analytical chemistry is useful in all the branchesof science like chemistry, physics, biology, geology, materials science, nuclear science andtechnology, medicine, environment and industry. Analytical measurements are aimed atobtainingqualitative and quantitative information about the composition and structure ofvarious materials that have relevance to both fundamental understanding as well as applicationstowards improving the quality of life. Analytical chemistry is of interdisciplinary nature and oftenis called central science that contributes to every branch of science. Today, analyticalchemistry has a range of powerful tools to obtain the needed information. Obtaining preciseand reliable data is the prime requirement in any analytical method for obvious reasons. Thisaspect is pertinent to nuclear industry and contributes significantly in various stages of nuclearfuel cycle. It is also essential to evaluate essence of the problem and choose the right methodthat is fit for the purpose. Therefore analytical scientists need a good working knowledge of theavailable techniques, awareness about the advancements made in instrumentation andmethodologies, and have to adapt “continued education and update” approach by which eachanalytical scientist could update oneself with the theoretical and experimental knowledgeassociated with the state-of-the-art analytical methodologies. Chemistry in general andAnalytical Chemistry in particular, is an experimental science. Therefore to better understandAnalytical Chemistry, it is essential to have an opportunity to experience various experimentalaspects so that the observations made could be analysed in the theoretical frame besidesexamining whether the data obtained are useful for the intended purpose. Over the years, thereis a paradigm shift in the analysis from classical chemistry to instrumental methods of analysis.As instrumental methods are ratio methods, there is a need to have standards / referencematerials to develop calibration methods. Although instrumental methods of analysis helpachieving reduced detection limits, classical methods are absolute methods for quantitativeanalysis and the principles in qualitative analysis are very important in various steps ofinstrumental analysis.Thus, major requirements for effective analysis are understanding the underlyingprinciple of the chosen method for a particular analysis and various steps that are needed likeselecting the method for collecting the sample, preparation of experimental sample, dissolutionmethod if required, signal generation, quantitative measurement of the signal, converting thesignal to concentration, analysis of data and reporting the data with stated uncertainty. Duringthe last century with the advent of electronics, improvements in computer technology andautomation of instrumental methods of analysis, a large number of instrumental methods areavailable to analytical chemists. Veracity of analytical data not only depends on choosing thecorrect instrumental method, materials, procedures and evaluating the measured results intoconcentrations of the analytes but more on understanding the phenomenon of signal generationand deciphering the signal from background. Materials that are suitable to obtain informationquantitatively / proportionally are good detector materials. Electronic devices are used todecipher the signal from noise, digitize and convert them into concentration of the analyte usinga suitable programme.

2Experiments in Analytical ChemistryIt is essential to have clarity and use the right terminology, like grammar in a language.For example, there is confusion between analytical technique and analytical method. Ananalytical technique is a fundamental scientific phenomenon that is useful for providinginformation on composition of substances whereas a method is a specific application of thetechnique. ICP MS is a technique used to determine large number of elements in wide variety ofmatrices, and determination of impurities in ground water using ICP MS is a method. Similarlyprocedure and protocol are not well distinguished by many. A procedure is a set of writteninstructions for carrying out a method (essentially meant for those with some background). Onthe other hand, detailed specific description of the method is a protocol and the instructionshave to be followed without any exception. Yet another pair of terms is precision andaccuracy. A few commonly used terminologies are given in the Table 1.1.Table 1.1 : Some commonly used definitionsAnalysisA process that provides chemical or physical information about theconstituents in the sample.DeterminationAn analysis of a sample to find the identity, concentration, or propertiesof the analyteMeasurementAn experimental determination of an analyte’s chemical or physicalproperties.TechniqueA chemical or physical principle used to analyze a sample.MethodMeans for analyzing a sample for an analyte in a matrixProcedureWritten directions outlining how to analyze a sample.ProtocolA set of written guidelines for analyzing a sample by an agencySignalAn experimental measurement that is proportional to the amount ofanalyteTotal analysisA technique in which the signal is proportional to the absolute amount oftechniqueanalyte (“classical” techniques)ConcentrationA technique in which the signal is proportional to the analyte’stechniqueconcentration; also called “instrumental” techniques.PrecisionAn indication of the reproducibility of a measurement.AccuracyA measure of the agreement between an experimental result and itsexpected valueSensitivityA method’s ability to distinguish between two samples reported as thechange in signal per unit change in the amount of analyte.Detection limitA statistical statement about the smallest amount of an analyte that canbe determined with confidenceMethod’sA measure of a method’s freedom from interferencesselectivityRobust methodA method that can be applied to analytes in a wide variety of matricesRugged methodA method that is insensitive to changes in experimental conditionsMethod blankA sample that contains all components of the matrix except the analyteCalibrationThe process of ensuring that the signal measured by a piece ofequipment or an instrument is correct.StandardisationThe process of establishing the relationship between the amount ofanalyte and a method’s signal

Experiments in Analytical ChemistryValidationQA/QCMeanMedianRangeStd. dev (s)ErrorVarianceSampling errorMethod errorPersonal errorMeasurement errorDeterminate rmal distributionDegrees offreedomSignificance testNull hypothesisSRM / CRMType 1 errorType 2 errort- testF - test3The process of verifying that a procedure yields acceptable results.Those steps taken to ensure that the work conducted in an analyticallab is capable of producing acceptable results.The average of a set of dataMiddle value(s) when a set of data is arranged in ascending ordescending orderDifference between the largest and smallest values in a set of dataA statistical measure of average deviation from the mean of a set ofdataA measure of bias in a resultSquare of standard deviation (s)Error occurred during sampling processError due to limitations of the analytical methodError due to analyst & his/her approachError due to limitations in the equipment / instrument usedError that can be traced to the source – above FOURA datum which is far larger / smaller than the remaining dataThe precision for analysis in which the only source of variability is theanalysis of replicate samplesPrecision of results of several samples, several analysts or severalmethods.Sources are not known but affects the scatter around the central value(mean)The range of possible values for a measurementRange of results around a mean value that can be explained by randomerrorProfile of frequency as a function of the range of measured valuesNormalised frequency ( probability) of measured valuesNumber of independent values on which the result is basedA statistical test to determine whether the difference between twovalues is significant or not.A statement that the difference between two values can be explained byindeterminate errorMaterial certified with known concentrations of the analytesThe risk of falsely rejecting null hypothesisThe risk of falsely retaining the null hypothesisFor comparing two mean valuesFor comparing two variancesIt is important to have documented haromonised procedures. It is crucial to documentprocedures and observations as it is essential for further calculations as well as for archiving.

4Experiments in Analytical ChemistryAnalytical chemistry has become a multi disciplinary subject in which chemicalinstrumentation has made great inroads. It is essential that efforts be made to identify theappropriate methods and methodologies for obtaining quality analytical data that are precise,accurate and reliable, which would stand to the scrutiny by regulators in various branches ofscience and technology. An attempt is made to introduce briefly some aspects on topics likeclassical methods, instrumental methods, signal generation and quality assurance & qualitycontrol in analytical chemistry in this part. In the second part, a few experiments are includedcovering most of the areas that an analyst would like to be exposed in the induction period intothe subject.Basic Tools in Analytical Chemistry1BAs Analytical Chemistry is a quantitative science, it deals with numerical andexperimental tools. Measurements and numerical calculations are integral part of everydetermination e.g. concentration of a species in a solution, evaluating equilibrium constant,reaction rates, and so on so forth.UnitsMeasurement data consists of a number and a unit to express the quantity e.g. mass ofa sample is 5.2mg. Unfortunately a few different units like oz are also used for the samequantity. In order to have to use the same units, a common set of fundamental units, called SIunits are defined which are given in Table 1.2. Some more derived units and their equivalent SIunits are given in Table 1.3. It is advisable to practice to use only these units so that the basictool of numbers will be on same scale and international comparison of results is easy.Table 1.2 Fundamental SI urrentamount of oleTable 1.3 : Other SI and Non-SI urepascalatmosphereenergy, work, aturedegree Celsiusdegree ivalent SI Unit1 Å 1 10-10 m1 N 1 m . kg/s21 Pa 1 N/m2 1 kg/(m.s2)1 atm 101, 325 Pa1 J 1 N . m 1 m2 . kg/s21 W 1 J/s 1 m2 . kg/s31C 1A.s1 V 1 W/A 1 m2 . kg/(s3. A)oC K – 273.15oF 1.8(K-273.15) 32

Experiments in Analytical Chemistry5Significant FiguresThe analytical data of a measurement are expected to provide magnitude anduncertainty. If

Analytical Chemistry with an objective of providing a forum for revisiting fundamentals of analytical chemistry and exchanging with experts, the latest developments in analytical chemistry and its applications. In addition to regular lectures on various aspects of analytical chemistry, laboratory experiments were included in this School to .