ATOMIC ABSORPTION SPECTROSCOPY

ATOMIC ABSORPTION
SPECTROSCOPY
(AAS)
LE THI THAO NGUYEN
1101760017


APPLICATION

•

CONCLUSION

•

4

3

2

1

• TECHNIQUE
• INTRODUCTION

CONTENTS


• INTRODUCTION

1

Monochromator

Detector

Lamp
Flame

Atomic absorption
spectroscopy


1

• INTRODUCTION

Excited State

 

E

Excitation

Ground State

Emission

E1

E0


2

• TECHNIQUE

Principle

Flame
Atomizer

Detector & Recorder

Hollow Cathode Lamp

Monochromator

Nebulizer
Sample
Hollow Cathode Lamp

Each element has its own unique lamp

Nebulizer

Monochromatic

It creates a fine spray

To select the specific wavelength of light.

of the sample.

The selection of the specific wavelength
allows the determination of the element.

Atomizer

It breaks down the molecules into the atoms.

Detector

To convert the light signal to electrical signal
proportional to the light intensity.


2

• TECHNIQUE

Notices

Sample
(solution)
HCl < HNO3 < H2SO4 < H3PO4 < HF


2

• TECHNIQUE

Determination

Calibration curve method

A=K.C

STEP 1

•

A: intensity
K: constant

Prepare 5 standard samples with different determined concentrations
(C1,C2,C3,C4,C5…).

C Concentration of element in sample

•

Measuring intensity of absorption of each standard samples
(A1,A2,A3,A4,A5…).

•

Draw a graph indicate the relationship between concentration and
intensity: y=ax

Intensity

STEP 2

y=ax

Concentration

•
•

Measure 3 times intensity of real samples.
Determine the concentration of real sample by using calibration
curve.


3

•

APPLICATION

1. Determine Ca2+ in hard water.

Prepare 6 standard samples

422.7 Wavelength (nm)

Real Sample

1.
2.

Evaporate the liquid sample, until obtain m(g) solid.
Dissolve m(g) solid in hydrochloride acid (1%).


•

3

APPLICATION
Flame
Atomizer

Detector & Recorder

Hollow Cathode Lamp

Monochromator

Nebulizer

Absorption intensity

Sample

f(x) = 4.75x + 0.01
R² = 1

Concentraton (μg/ml)

Standard sample


Absorption intensity

3

•

APPLICATION

f(x) = 4.75x + 0.01
R² = 1

•

 
Absorption of real sample is 0.75

(A=0,75)

•

0.75

0.75
-> X (C real sample) = 0.156 (μg/ml)

•

Concentraton (μg/ml)

Use graph to determine concentration of real sample


4

•

CONCLUSION