UNIT 1 - Introduction to Analytical Chemistry.pdf

UNIT 1 - Introduction to Analytical Chemistry.pdf
For Med tech students

1. UNIT 1:
The Nature
of Analytical
Chemistry

2. Outline
✔TheRoleofAnalyticalChemistry
✔QuantitativeAnalyticalMethods
✔ATypicalQuantitativeAnalysis
✔AnIntegralRoleforChemical
Analysis:FeedbackControlSystem

3. 1A: The Role
Of Analytical
Chemistry

4. What is
Analytical Chemistry?
1A: The Role of Analytical Chemistry
Task:Createaconceptmapaboutanalytical
chemistryasadisciplineanditssignificant
applicationsinhouseholds,industries,and
otherdisciplines,etc.
(10mins.)

5. Analytical Chemistry
Itisameasurementscience
consistingofasetofpowerful
ideasandmethodsthatare
usefulinallfieldsofscience,
engineering,andmedicine.
1A: The Role of Analytical Chemistry

6. 1A: The Role of Analytical Chemistry

7. 1A: The Role of Analytical Chemistry

8. 2 Types of Chemical Analysis
1A: The Role of Analytical Chemistry
QualitativeAnalysis–revealsthe
identityoftheelementsand
compoundsinasample.
QuantitativeAnalysis–indicates
theamountofeachsubstanceina
sample.

9. 1A: The Role of Analytical Chemistry

10. 1A: The Role of Analytical Chemistry

11. 1B: Quantitative
Analytical
Methods

12. 1B: Quantitative Analytical Methods
Challenge:Devisewayson
howyoucandetermine
themassofthebarium
presentinabarium
chloridesolutionofan
unknownvolume.
(10mins.)

13. Quantitative Analytical Methods
1B: Quantitative Analytical Methods
GravimetricMethods–determine
themassoftheanalyteorsome
compoundchemicallyrelatedto
it.

14. Quantitative Analytical Methods
1B: Quantitative Analytical Methods
VolumetricMethod–measures
thevolumeofasolution
containingsufficientreagentto
reactcompletelywiththeanalyte.

15. Quantitative Analytical Methods
1B: Quantitative Analytical Methods
ElectroanalyticalMethods –
measureelectricalproperties
suchaspotential,current,
resistance,andquantityof
electricalcharge.

16. Quantitative Analytical Methods
1B: Quantitative Analytical Methods
SpectroscopicMethods–explore
theinteractionbetweenEM
radiationandanalyteatomsor
moleculesortheemissionof
radiationbyanalytes.

17. 1C: A Typical
Quantitative
Analysis

18. 1C: A Typical Quantitative Analysis
Recall:Listdown
thestepsin
conducting a
scientificmethod.
Giveatleastone
concreteexample.
(10mins.)

19. 1C: A Typical Quantitative Analysis

20. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
1.ChooseaMethod
Considerations:requiredaccuracylevel,
number of samples, sample
complexity/components
Challenges:intuition-based, large
investmenttime/money

21. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
2.AcquireSample(rep.sample)
Considerations:large/bulkandheterogenous-
>greateffortisrequiredtogetthe
representativesample
Solution:Sampling(processofcollectinga
smallmassofamaterialwhosecomposition
accuratelyrepresentsthebulkofthematerial
beingsampled);Assay(processofdetermining
howmuchofagivensampleisthematerialby
itsindicatedname)

22. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
3.ProcessingtheSample
3.1PreparingaLabSample
-solidsamplesmustbegroundtodecrease
sizeandensurehomogeneityandstoredfor
variouslengthsoftimebeforeanalysisbegins.
-drysamplebeforethestartofanalysis
-Ifliquid/gassamples,keepinsealed
containerstopreventcontamination

23. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
3.ProcessingtheSample
3.2DefiningReplicateSamples
-Replicationimprovesthequalityofthe
resultsandprovidesameasureoftheir
reliability.

24. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
3.ProcessingtheSample
3.3PreparingSolutions:Physical&Chemical
Changes
-Dissolution

25. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
4.EliminatingInterferences
-Speciesotherthantheanalytethataffectthe
finalmeasurementarecalledinterferences,or
interferents.
Matrix/samplematrix–isthecollectionofall
thecomponentsinthesamplecontainingan
analyte.

26. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
4.EliminatingInterferences
-Techniquesorreactionsthatworkforonly
oneanalytearesaidtobespecific.Techniques
orreactionsthatapplytoonlyafewanalytes
areselective.

27. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
5.CalibratingandMeasuring
Concentration
-Allanalyticalresultsdependonthefinal
measurementXofaphysicalorchemical
propertyoftheanalyte.
-ThemeasurementofthepropertyXis
directlyproportionaltotheconcentration??????
??????:
??????
??????=????????????
where ??????is a proportionality constant

28. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
6.CalculatingResults
-Computinganalyteconcentrationsfrom
experimentaldataisusuallyrelativelyeasy,
particularlywithcomputers.
-Computationsarebasedonraw
experimentaldatacollectedinthe
measurementstep,characteristicsofthe
measurement instruments,and the
stoichiometryoftheanalyticalreaction.

29. Steps in Conducting a Quantitative Analysis
1C: A Typical Quantitative Analysis
7.EvaluatingResultsbyEstimating
Reliability
-Analyticalresultsarecompleteonlywhen
theirreliabilityhasbeenestimated.

30. 1D: An Integral Role for
Chemical Analysis:
Feedback Control
Systems

31. An Integral Role for Chemical Analysis
1D: An Integral Role for Chemical Analysis: Feedback Control Systems

32. FeedbackControlSystem–referstothe
processofcontinuousmeasurementand
control.
FeedbackLoop–referstothecycleof
measurement,comparison,andcontrol.
1D: An Integral Role for Chemical Analysis: Feedback Control Systems
An Integral Role for Chemical Analysis

33. Reference
Skoog,D.A.,West,D.M.,Holler,F.J.,
Crouch,S.R.(2021).Fundamentalsof
AnalyticalChemistry(10thed.).Cengage
Learning.