Atomic absorption spectrometry


________ (1) cathode lamps are a high-intensity, stable-light source that emits the
element-specific spectral lines required for atomic absorption spectrometry.

A flame AAS instrument must never be left _________ (2) while the flame is burning.

Install and remove the burner.

If you cannot ________ (3) flame after two attempts, it is likely that there is some problem with
the ________(4), ignition system, or gas supplies.

Clean external and _________ (5) surfaces of the burner.

Inspect the gas supply hoses regularly, and replace any that are ________ (6) or damaged.

We recommend that all gas supply hoses are replaced every four years.

Periodically check the external drain tube.

Syringe purge

A command is provided in the system software to purge the syringe to remove any ______ (7) and
contamination before use.

Capillary tip alignment

The autosampler capillary tip must be ________ (8) with the cuvette injection hole before use, and
the capillary tip depth adjustment set correctly so that the sample is injected properly onto the
floor of the cuvette.


The operating system of electrothermal atomisation in a graphite furnace _________ (9) of three
phases:

The drying phase, at 100 °C, to remove the solvent

The ___________ (10) , or pyrolysis phase, at a higher temperature, to remove organic matrix

The third phase atomisation, to convert the residue into an atomic vapour



Read the text and answer the questions:


1 What kind of spectral lines do you need for atomic absorption spectrometry?

2 What are the possible reasons, if you cannot ignite flame?

3 Do you have to change the gas supply hose every year?

4 When do you have to purge the syringe? Why?

5 Where do you inject the sample? How is this made?

6 How many phases are there in electrothermal atomization? What are they?


Vocabulary warm-up:

hollow                         light source                 unattended      ignite
vapour

burn                cracked           damaged                     capillary tip
syringe purge                                           burner

hose                bubbles                                  alignment        solvent


replace                  convert                        ashing              depth

                                               adjustment       graphite furnace


Definitions – fill in the missing word:


1 If a tree trunk has no wood in it, it is ____________

2 Keep an eye on the fire, don’t leave it _____________

3 The part of a cooker or a stove that produces a flame is called a/an _____________

4 A long tube made of rubber, plastic is called a/an ___________

5 A plastic tube with a long needle is a/an ____________

6 _____________ is the extreme part of a capillary.

7 ____________ a mass of very small drops of liquid in the air

8 ____________ is a process where a substance is converted into ashes.

9 A ball of air or gas in a liquid is called a/an _________________

10 ___________ provides light.