1. Instrumentation
Deals with the theoretical and practical aspects of
different instruments and instrumental techniques
involved in Analytical Chemistry,
Which is a branch of chemistry involving separation,
identification and determination of components of a
sample
10. Classification of analyte
• Major component 1-100%
• Minor component 0.01 to <1.00%
• Trace component 1ppb – 100 ppm
• Ultra-trace component <1ppb
11. Analytical method on the basis of sample
size
Method Weight mg Volume µl
Meso >100 >100
Semi-micro 10-100 50-100
Micro 1-<10 <50
Ultra micro <1
13. Problems
• Prepare a solution of 1 Molar HCl
• Prepare a solution of 1 Molar NaOH
• Prepare a solution of 1 Molar H2SO4
• Prepare a solution of 1 Molar Oxalic acid
dihydrate
• Prepare a solution of 1 Normal Oxalic acid
dihydrate
15. Problem
• You have a stock solution of NaOH having
concentration of 1 M, prepare 500 mL solutions of
0.1N, 0.2N, 0.3N using dilution equation
17. Problem
• What is pCl and pNa of a 5.00g/L solution
of NaCl?
Na Cl NaCl Given Molar pNa/pCl
23 35.5 58.5 5g/L 0.085470 1.068186
18. Selecting an Analytical Technique
Defining the problem first:
1. What accuracy and precision is required?
2. How much sample is available?
3. What is the concentration range of the
analyte?
4. What components of the sample cause
interference?
5. What are the physical and chemical
properties of the sample matrix or interfering
species?
6. How many samples are to be analyzed?
19. Numerical Criteria for Selecting Analytical
Technique
1. Precision
2. Bias (A systematic error occurring in a chemical
measurement that is inherent in the method itself or
caused by some artifact in the system, such as a
temperature effect)
3. Sensitivity (LOD and LOQ)
4. Detection Limits
5. Concentration Range
6. Selectivity
20. Other Characteristics to Be
Considered in Method of Choice
1. Speed
2. Ease and Convenience
3. Cost and availability of instrument
4. Per-sample cost
21. Sampling
• Homogeneous materials (grab sample,
random)
• Heterogeneous materials (Several samples
are required) that include
1- Gross sampling
2- Laboratory sample (taken from gross sampling and
homogenized)
3- Analysis samples (taken from laboratory sample)
4- Biological fluids (sampling time and preservation)
5- Storage of the samples (suitable containers, low
temp)
6- Urine samples (acidified pH4.5)
22. Preparation of samples
• Weighing of the sample
• Samples are prepared in replicates
• Solid samples must be dissolved
• Ashing or digestion for trace metals
• Preparation of blank
23. Chemical separation
• Includes precipitation, extraction,
chromatography, dialysis and distillation,
and
1- Eliminates interferences (analyte away
from matrix)
2- Provides suitable selectivity in
measurement
25. Data Analysis
• The concentration of analyte in the sample
solution is used to calculate the concentration of
analyte in the original sample, and is expressed
in relative terms
• Precision is expressed by SD of RSD
• Finally
Critical evaluation of results (To see whether
results relate to the analytical problem, as stated
before the experiment