AAS

Question 1

It is an analytical technique that measures the concentrations of
elements. It makes use of the absorption of light by these elements in order to measure their
concentration.

Answer 1

ATOMIC ABSORPTION SPECTROSCOPY (AAS)

Question 2

It quantifies the absorption of ground state atoms in the gaseous state.

Answer 2

ATOMIC ABSORPTION SPECTROSCOPY (AAS)

Question 3

These are usually determined from a working curve after calibrating the instrument with standards of known concentration.

Answer 3

Concentration measurements

Question 4

They absorb ultraviolet or visible light and make transitions to higher electronic energy levels.

Answer 4

atoms

Question 5

It is determined from the amount of absorption.

Answer 5

Analyte Concentration

Question 6

It is a very common technique for detecting metals and metalloids in environmental samples.

Answer 6

Atomic absorption

Question 7

4 principal components of Atomic absorption spectrometers

Answer 7

1- A light source ( usually a hollow cathode lamp)
2 - An atom cell (atomizer )
3 - A monochromator
4 - A detector, and read out device.

Question 8

The usual light source of the element that is being measured

Answer 8

hollow cathode lamp

Question 9

It contains a tungsten anode and a hollow cylindrical cathode made of the element to be determined. These are sealed in a glass tube filled with an inert gas (neon or argon).

Answer 9

Hollow cathode lamp

Question 10

Elements to be analyzed needs to be in ___

Answer 10

atomic sate

Question 11

It is the separation of particles into individual molecules and breaking molecules into atoms.

• This is done by exposing the analyte to high temperatures in a flame or graphite furnace.

Answer 11

Atomization

Question 12

two types of atomization:

Answer 12

Flame and Graphite Furnace Atomization

Question 13

Gas/Air

Answer 13

1700-1900

Question 14

Gas/O2

Answer 14

2700-2800

Question 15

H2/Air

Answer 15

2000-2100

Question 16

H2/O2

Answer 16

2550-2700

Question 17

C2H2/Air

Answer 17

2100-2400

Question 18

C2H2/O2

Answer 18

3050/3150

Question 19

C2H2/N2O

Answer 19

2600-2800

Question 20

It uses excited atoms

Answer 20

Atomic Emission

Question 21

It uses ground-state atoms

Answer 21

Atomic Absorption

Question 22

The fine mist of droplets is mixed with ___ and ____ and burned.

Answer 22

fuel (acetylene), and oxidant (nitrous oxide)

Question 23

It is important because it influences the distribution of atoms.
- It can be manipulated by oxidant and fuel ratio.

Answer 23

Flame temperature

Question 24

any factor that affects the ground state atom population

Answer 24

Interference

Question 25

Factors that may affect the ability of the instrument to read this parameter

Answer 25

Interference

Question 26

Element other than the one of interest may absorb the wavelength being used.

Answer 26

Absorption and Source Radiation

Question 27

the formation of ions rather than atoms causes lower absorption of radiation. This problem is overcome by adding ionization suppressors.

Answer 27

Ionization Interference

Question 28

the atoms of the same kind that are absorbing radiation will absorb more at the center of the line than at the wings and thus resulting in the change of shape of the line as well as its intensity.

Answer 28

Self Absorption

Question 29

This is caused by the presence of a particle from incomplete atomization .This problem is overcome by increasing the flame temperature

Answer 29

Background Absorption of Source Radiation

Question 30

Rate of aspiration, nebulization, or transport of the sample (e g viscosity, surface tension, vapor pressure , and density)

Answer 30

Transport Interference

Question 31

Analyzing metals in biological fluids such as blood and urine.

Answer 31

Clinical Analysis

Question 32

Monitoring our environment -e g finding out the levels of various elements in rivers, seawater, drinking water, air, and petrol.

Answer 32

Environmental Analysis

Question 33

In some pharmaceutical manufacturing processes, minute quantities of a catalyst used in the process (usually a metal) are sometimes present in the final product. By using AAS the amount of catalyst present can be determined.

Answer 33

Pharmaceuticals

Question 34

Many raw materials are examined and AAS is widely used to check that the major elements are present and that toxic impurities are lower than specified - e q in concrete, where calcium is a major constituent, the lead level should be low because it is toxic.

Answer 34

Industry

Question 35

It is the analyte that you want to analyze

Answer 35

Standard of Known Concentration