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Analytical Chemistry - I
Syllabus
Subject
Title
Prof. Name
Analytical
Chemistry I
3hrs / week
Myeong Hee
Moon
2123 - 5634
Text: Quantitative Chemical Analysis 8th ed.
Harris. Must Use English Version Textbook
Reference: Analytical Chemistry (Christian) 7th
Lecture
Fundamentals of Analytical Chemistry (Skoog) 8th
Info.
1st exam: 25%
2nd exam: 25%
Final: 25%
Attendance
Evaluation (including Quiz)
25 %
Lecture note can be obtained from homepage
http://chem.yonsei.ac.kr/~mhmoon
Total 100 %
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Syllabus
Week
Days
CONTENTS
1
3. 4∼3.8
2
3.11∼3.15
3
3.18 ∼3.22 Statistics/Quality Assurance & Calibration
4
3.25∼3.29
5
4.1∼4.5
6
4.8∼4.12
7
4.15∼4.19
Monoprotic Acid-Base Equilibria
8
4.22∼4.26
Midterm
Remark
Introduction
The Analytical Process/chemical
measurements
Experimental Error/Statistics
Quality Assurance & Calibration
Chemical Equilibrium
04.02:
1st exam
Activity & Systematic treatment of Equilibrium
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Syllabus
9
4.29∼5.3
Polyprotic Acid-base Equiilibria
10
5.6∼5.10
Acid-base Titrations
11
5.13∼5.17 EDTA Titrations
12
5.20∼5.24 Advcanced Topics in Equilibrium
13
5.27∼5.31 Fundamentals of Electrochemistry
14
6.3∼6.7
05.7
2nd exam
Electrodes and Potentiometry
15
6.10∼6.14 Electrodes and Potentiometry
16
6.17∼6.21 Final Exam
06.11
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Ch 0. Fundamentals in Analytical Chemistry
Topics :
Stages in Chemical Analysis
Concentrations
Stoichiometric Calculations
Titrations
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Analytical Chemistry Applied to:
Chemistry,
Biology
Medicine (hospital),
Geology (geological survey)
Oceanography,
Material Science
Forensic Science,
Archeology
Farming,
Food Science
Environmental Science, etc
(Government regulations on pollution)
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ANALYZE ?
What is it (chemical elements) ? Qualitative analysis
How much is present ?
Quantitative analysis
Development of New Products ?
– want to know composition of mixtures
or giving possibility of impurities
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0-2. analytical Chemist’s Job
analyte
: the species being measured in a chemical analysis
(chemical substance)
*
Stages in chemical analysis
Decide First Level of Results needed.
• Level of accuracy
• Economical Aspect
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How much caffeine is in a chocolate bar ?
1. Sampling
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Sample preparation
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Steps in chemical analysis
1. Formulating the question
2. Selecting analytical procedure: literature survey
3. Sampling
4. Sample Preparation
: converting sample into a form suitable for chemical analysis
- drying, sample weighing, mixing
3. Chemical Analysis
4. Calibration Curves
5. Interpreting the Results
6. Draw conclusions
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Ch 1. Chemical Measurements
1-1 SI Units (Systeme International d'Unites)
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Conversion between Units
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1-2. Chemical Concentrations
1) Molarity (M)
# of moles per a liter of solution
moles of solute (1 mole = g/fw)
Molarity 
1 Liter=103cm3 = 1000cc
L
molecular weight - for moles
formula weight
- for electrolytes
(since no molecule exists in electrolyte sol.)
2) Molality (m)
# of moles per a kg of solvent.
m
temp. independent
# of moles
kg (solvent )
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3) Percent Composition
wt (%) 
mass of solute
 100
mass of total mixtures
vol (%) 
volume of solute
 100
volume of total solution
4) ppm & ppb
ppm 
mass of substituent
 10 6
mass of sample
ppb 
mass of substituent
 10 9
mass of sample
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1-3. Preparing Solutions
Dilution
Mconc Vconc = Mdil Vdil
ex) A solution of ammonia in water is called "ammonium hydroxide" because
of the equilibrium :
NH3 + H2O  NH4+ + OHThe density of concentrated ammonium hydroxide, which contains 28.0 wt%
NH3, is 0.899 g/mL. What volume of this reagent should be diluted to make 500
mL of 0.250 M NH3 ? (Ans: 8.45mL)
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1-4. solutions & Stoichiometry
1) Volumetric calculation
a A + b B  products
mol
A
=
a
mol
b
B
ex) In acid solution, potassium permanganate reacts with H2O2 to form Mn2+:
5H2O2 + 2 MnO4- + 6 H+  5O2 + 2Mn2+ + 8 H2O
In neutral solution, it reacts with MnSO4 to form MnO2:
3Mn2+ + 2 MnO4- + 4 OH-  5 MnO2 + 2 H2O
Calculate the number of milliliters of 0.100 M KMnO4 that will react with 50.0
mL of 0.200 M H2O2 and 50.0 ml of 0.200 M MnSO4.
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2) gravimetric calculation
Cl2  2 AgCl (s)
mol cl2 =
1
mol AgCl
2
g cl 2
Gravimetric factor
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Additional Exercise in Stoichiometric Calculations
1. A 0.2638-g soda ash sample is analyzed by titrating the sodium carbonate
with the standard 0.1288 M hydrochloric acid solution, requiring 38.27 mL.
Calculate the percent sodium carbonate in the sample.
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2. A 0.200-g sample of pyrolusite is analyzed for manganese content as follows.
Add 50.0 mL of a 0.100 M solution of ferrous ammonium sulfate to reduce the
MnO2 to Mn2+. After reduction is complete, the excess ferrous ion is titrated in
acid solution with 0.0200 M KMnO4, requiring 15.0 mL. Calculate the percent
manganese in the sample as Mn3O4 (only part or none of the manganese may
exist in this form, but we can make calculations on the assumption that it
does). (Ans: 66.7%)
2 Fe2+ + MnO2 + 4 H+  2 Fe3+ + Mn2+ + 2 H2O
5 Fe2+ + MnO4- + 8 H+  5 Fe3+ + Mn2+ + 4 H2O
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1.5 Titrations
titration
acid-base
redox
precipitation
Spectrophotometric
 biochemistry
: Addition of titrant to analyte
for calculation of conc.
Calculate conc. of analyte from
how much it is consumed.
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1.5 Titrations
Calculation of analyte conc. from how much titrant is consumed.
By HOW to DETECT ?
1. detecting sudden change in V or I
2. color change (indicator)
3. change in Absorbance
* Equivalence Point : ideal, stoichiometric.
: occurs when the quantity of titrant added is the exact amount
necessary for stoichiometric rxn with analyte.
* End Point : actually observable point.
Sudden change in color or voltage.
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1.5 Titrations
In case of titration,
conc. of titrant should be known first.
 Is it accurate ?
Use primary standard.
99.9 % or better in purity.
Stable when dried by heating or vacuum
* In case of titrant which is not primary std.
Use standardization
titrate a proper primary std with the titrant.
Then calculate the conc. of titrant.
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1-6.
Titration Calculations
key step :
molestitrant
=
molesanalyte
ex) standardization of titrant - analysis of unknown
- Determination of Ca content in Urine
oxalate
1. Ca+2 + C2O42-  Ca(C2O4)H2O (s)
2. precipitate in ice-cold water and wash
(to remove free oxalate) then redissolve in acid
3. heat to 600C, and titrate with standardized KMnO4
until purple end.
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1-6.
Titration Calculations
Q1: standardization ?
Suppose 0.3562 g Na2C2O4 (fw=134.00) in 250.0 mL flask.
Calculate molarity of KMnO4
when 10.0 mL of the sol. consumes 48.36 mL of KMnO4.
5 C2O4-2 + 2 MnO4- + 16 H+  10 CO2 + 2 Mn+2 + 8 H2O
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Q2: Analysis of unknown.
Suppose Ca in 5.00 mL urine is precipitated and it
requires 16.17mL of std. MnO4- solution.
[Ca+] in urine ???
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Homework
In the Textbook: 1-19, 20, 30, 31, 34, 42, 45
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