chapter 1.1-intro analy

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CHAPTER 1 : INTRODUCTIONOverview of the Fundamental ofAnalti!al Chemi"tr # It"

A$$li!ation

CHAPTER 1


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•Defnition:

Analytical chemistry isthat it is “qualitative and

quantitativecharacterization ofmatter”.

•Characterization meansnd composition and

identity of chemicalcompounds / elements present in a sample.

•Forensics, quality control,medical tests

TOPIC 1%1

Introdu!tion to Analti!al

Chemi"tr


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An analysis involves several

steps and operations which

depend on:

•the particular problem

• your expertise

• the apparatus or

equipment available.

The analyst should be

involved in every step.

An analysis involves several

steps and operations which

depend on:

•the particular problem

• your expertise• the apparatus or

equipment available.

The analyst should be

involved in every step.

Fig. 1.1. Steps in an analysis


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•Qualitatie analysis:

!"s the identifcation o# one $ morechemical species present in a material.

!%o tell us &HAT is present in asample.

•Quantitatie analysis:

!"s the determination o# the e&act

amount o# a chemical species presentin a sample.

! %o tell us HO& 'UCH o# a species ispresent in a sample.

&hat i" Analti!al Chemi"tr(


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Qualitative analysis is what.

Quantitative analysis is how much.

Qualitative analysis is what.

Quantitative analysis is how much.


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Ta)le 1: 'ethod" ofAnal"i"

Qualitative Method Quantitative Method

Qualitative analysis:

•Is an identification method

•established the chemicalidentity of species in the

samples•such analysis does not reportthe amount of substance

•

Example:Identify the present ofpreservatives in soft drink

Quantitative analysis :

•determine the relative amountof these species or analyte, innumeral terms

•undertaken when the identityof the component is alreadyknown and when it isimportant to also know thequantities of theseExample:• nalysis of soil reported thatnitro!en concentration presentis at "#$ ppm


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Cla""i*!ation ofAnalti!al

'ethod"

Cla""i!al'ethod

In"trumental

'ethod


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Ta)le +: Cla""i*!ation ofAnalti!al 'ethod"

Classical Methods Instrumental Methods

• called as %wet chemical methods&•'nalyte was separate from (ample by :precipitation, extraction or distillation.

Qualitative analyses:

)he analyte then treated rea!ent that yieldproduct that could be reco!nised by colour,meltin! point, solubilities, odours etc.

Example: Qualitative analysis of commonions * +b$, -!$, !

Quantitative analysis:

mount of nalyte can be determined by!ravimetric and titrametric method

/easurement of physical propertiesof analyte 0 conductivity, electrodepotential li!ht absorption or emission,mass to char!e ratio1 be!an to usedfor quantitative analysis.

2hromato!raphic and electrophoretictechnique replaces distillation,extraction and precipitation andseparation of complex mixtures priorto quantitative and qualitative analysis


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Cla""i!al 'ethod"

Analyte is separated #rom Sample'y : precipitation, extraction ordistillation.

Qualitatie analysis:

%he analyte is then treated (ithreagents that yield product thatcould 'e recognised 'y Colour,melting point, solu'ilities, odoursetc.

E,am$le: Qualitatie analysis o#common ions ) *'+,-g+ ,Ag

Quantitatie analysis:

Amount o# Anal te can 'e


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In"trumental 'ethod ofAnal"i"Classiication o Instrumental Method

INSTRUMENTAL METHOD

SPECTROSCOPIC METHOD SEPARATION METHOD

• Molecular Spectroscopy• Atomic Spectroscopy

• Column Chromatography• Planar Chromatography


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chapter 1.1-intro analy

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