INSTRUMENTAL ANALYSIS ACS
EXAM FINAL | COMPLETE EXAM
QUESTIONS AND CORRECT
ANSWERS
What is linear range? - ANSWERAnalyte concentration over the response that is
proportional to the concentration.
When analyzing an unknown where should the concentration of the unknown fall? -
ANSWERSomewhere within the linear range
What should you do if the unknown concentration is below the linear range? -
ANSWERperform pre-concentration
Examples of pre-concentration - ANSWERevaporating, anodic stripping voltammetry
What should you do if the concentration of the unknown is greater than the linear
range? - ANSWERdilute the concentration so that it falls closer to the linear range
What is the electromagnetic spectrum in order of increasing wavelength? -
ANSWERgamma, x-rays, UV, visible light, IR, microwave, radio
What is the electromagnetic spectrum in order of increasing frequency? -
ANSWERradio, microwave, IR, visible, UV, x-rays, gamma
In what region of the electromagnetic spectrum is the resonant frequency of electrons in
glass? - ANSWERultraviolet
More about regions (answer IDK) - ANSWERIDK
How do you calculate the concentration of a sample given a point calibration? (answer
IDK) - ANSWERIDK
What are the common methods of atomization in atomic absorption? - ANSWERflame
atomization, electrothermal atomization, furnace atomization
What type of sample can be used for flame atomization? - ANSWERliquid
What type of sample can be used for electrothermal atomization - ANSWERsolid and
slurry
What type of sample can be used for furnace atomization? - ANSWERsolid and slurry
, What are the pros and cons of using electrothermal atomization and/or furnace
atomization compared to using flame atomization? - ANSWERBoth offer a lower
detection limit and can work with solid samples. However, both are slower due to
heating-cooling cycles and are less precise making them less producible.
Doppler effects - ANSWERan observed change in the frequency of a wave when the
source or observer is moving
What is the light source of atomic absorption? - ANSWERhallow cathode lamp
What results in greater Doppler effect in flame atomization? - ANSWERTemperature in
flame is greater than that in hallow cathode lamp which means that flames also have
wider spectral lines. This enables a greater doppler effect.
What is the difference between hollow cathode lamp and flame? - ANSWERHollow
cathode lamp has narrower spectral lines than the spectral lines found in flames
Spectral lines - ANSWERThe wavelengths where a specific element can absorb or emit
light
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *air*
Temperature, °C *1700-1900* - ANSWERnatural gas
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *oxygen*
Temperature, °C *2700-2800* - ANSWERnatural gas
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *air*
Temperature, °C *2000-2100* - ANSWERhydrogen
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *oxygen*
Temperature, °C *2550-2700* - ANSWERhydrogen
EXAM FINAL | COMPLETE EXAM
QUESTIONS AND CORRECT
ANSWERS
What is linear range? - ANSWERAnalyte concentration over the response that is
proportional to the concentration.
When analyzing an unknown where should the concentration of the unknown fall? -
ANSWERSomewhere within the linear range
What should you do if the unknown concentration is below the linear range? -
ANSWERperform pre-concentration
Examples of pre-concentration - ANSWERevaporating, anodic stripping voltammetry
What should you do if the concentration of the unknown is greater than the linear
range? - ANSWERdilute the concentration so that it falls closer to the linear range
What is the electromagnetic spectrum in order of increasing wavelength? -
ANSWERgamma, x-rays, UV, visible light, IR, microwave, radio
What is the electromagnetic spectrum in order of increasing frequency? -
ANSWERradio, microwave, IR, visible, UV, x-rays, gamma
In what region of the electromagnetic spectrum is the resonant frequency of electrons in
glass? - ANSWERultraviolet
More about regions (answer IDK) - ANSWERIDK
How do you calculate the concentration of a sample given a point calibration? (answer
IDK) - ANSWERIDK
What are the common methods of atomization in atomic absorption? - ANSWERflame
atomization, electrothermal atomization, furnace atomization
What type of sample can be used for flame atomization? - ANSWERliquid
What type of sample can be used for electrothermal atomization - ANSWERsolid and
slurry
What type of sample can be used for furnace atomization? - ANSWERsolid and slurry
, What are the pros and cons of using electrothermal atomization and/or furnace
atomization compared to using flame atomization? - ANSWERBoth offer a lower
detection limit and can work with solid samples. However, both are slower due to
heating-cooling cycles and are less precise making them less producible.
Doppler effects - ANSWERan observed change in the frequency of a wave when the
source or observer is moving
What is the light source of atomic absorption? - ANSWERhallow cathode lamp
What results in greater Doppler effect in flame atomization? - ANSWERTemperature in
flame is greater than that in hallow cathode lamp which means that flames also have
wider spectral lines. This enables a greater doppler effect.
What is the difference between hollow cathode lamp and flame? - ANSWERHollow
cathode lamp has narrower spectral lines than the spectral lines found in flames
Spectral lines - ANSWERThe wavelengths where a specific element can absorb or emit
light
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *air*
Temperature, °C *1700-1900* - ANSWERnatural gas
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *oxygen*
Temperature, °C *2700-2800* - ANSWERnatural gas
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *air*
Temperature, °C *2000-2100* - ANSWERhydrogen
Given the following information about the flame atomization below, name the fuel type
that should be used.
Oxidant *oxygen*
Temperature, °C *2550-2700* - ANSWERhydrogen
