Spectroscopic Method

Question 1

Study of the interaction of electromagnetic radiation and matter.

Answer 1

Spectroscopy

Question 2

Method when a photon is absorbed by an atom or molecule which undergoes transition from lower energy stateto higher energy state

Answer 2

Absorption spectroscopy

Question 3

Occurs when an atom or molecule in an excited state returns to a lower energy state, and the excess energy is often released as photon

Answer 3

Emission spectroscopy

Question 4

Emission following the absorption of a photon is called ____

Answer 4

Photoluminescence

Question 5

Emission following a chemical reaction is called

Answer 5

Chemiluminescence

Question 6

Choose the correct order of spectroscopic instrumentation.

A. Source, wavelength selector, sample container, detector, readout
B. Detector, source, wavelength selector, sample container, readout
C. Readout, detector, sample container, wavelength selector, source

Answer 6

A

Question 7

Source of radiation in spectroscopic methods can either be ____ or _____ sources

Answer 7

Continuum kr line sources

Question 8

Source of radiation in spectroscopic methods can either be ____ or _____ sources

Answer 8

Continuum or line sources

Question 9

Lamp that emits radiation over a broad range of wavelengths, with a relatively smooth variation in intensity

Answer 9

Continuum sources

Question 10

Lamp that emits radiation at selected wavelengths

Answer 10

Line sources

Question 11

Highly useful line sirce because of their high intensities, narrow bandwidth, abd coherent nature of outputs

Answer 11

Laser (light amplification by stimulated emission of radiation)

Question 12

Uses either absorption or constructive and destructive interference to control the range of selected wavelengths

Answer 12

Filter

Question 13

Since filter can’t perform continuous selection of wavelengths,____ is used.

Answer 13

Monochromator

Question 14

Sample container in spectroscopic methods that’s made of quartz, glass, and silica

Answer 14

Cuvette or cells

Question 15

A device that identifies, records, or indicates a change in one of the variables in it’s environment

Answer 15

Detector

Question 16

Converts various type of chemical and physical quantities into electrical signals

Answer 16

Transducers

Question 17

Transducers used for detecting UV/Vis radiation. About 10^6 to 10^7 electrons are produced at the anode for each photon that strikes it’s photocathode

Answer 17

Photomultiplier tube (PMT)

Question 18

Device that displays the signal from the transducer in a form that is easily interpreted.

Answer 18

Signal Processor

Question 19

Radiation from the instrument that is outside the the nominal wavelength band chosen for the determination

Answer 19

Stray light

Question 20

When a molecule absorbs EMR, the number of photons passing through the sample decreases. Measurement of this decrease is called

Answer 20

Absorbance

Question 21

Plot of absorbance as function of the photon’s energy is ____

Answer 21

Absorbance spectrum

Question 22

Ratio of the radiant power passing through a sample to that from the source

Answer 22

Transmittance

Question 23

More commonly used in expressing attenuation of radiation because it is a linear function of analytes concentration

Answer 23

Absorbance

Question 24

Simplest instrument in UV-VIS that uses a single optical path between source and detector

Answer 24

Filter photometer

Question 25

Instrument equipped with a fixed- wavelength monochromator

Answer 25

Single Beam spectrophotometer

Question 26

Instrument equipped with a scanning monochromator that allows for automated recording of spectra. More versatile than S-BS

Answer 26

Double beam spectrophotometer

Question 27

In this instrument, radiation passes through the sample and is dispersed by grating

Answer 27

Diode array spectrometer

Question 28

First step in all atomic spectroscopic procedures is _____, a process in which a sample is converted into gas-phase atoms or elementary ions

Answer 28

Atomization

Question 29

With this atomizer, samples are introduced in a steady, continuous stream.

Answer 29

Continuous atomizer

Question 30

With this atomizer, individual samples are injected by a syringe or autosampler

Answer 30

Discrete atomizer

Question 31

With this atomizer, individual samples are injected by a syringe or autosampler

Answer 31

Discrete atomizer

Question 32

Widely used for analysis of trace metals in a variety of sample matrices

Answer 32

Atomic Absorption Spectroscopy (flame)

Question 33

Ideally suited for a multi -elemental analysis because all analytes in a sample are excited simultaneously

Answer 33

Atomic emission spectroscopy

Question 34

Common light source for atomic measurements is __

Answer 34

Hollow cathode lamp Anion- tungsten Cation- Ne or Ar

Question 35

Hollow cathod lamp is a ___ lamp that permits determination of more than one element

Answer 35

Multi element

Question 36

AAS Instrumentation

Answer 36

Nebulization Desolation Volatilization Dissociation Ionization

Question 37

Differentiate AAS and AES

Answer 37

AAS Flame Furnace AES Plasma ES ICP-MS

Question 38

Electrically conducting gaseous mixture present in AES containing significant concentration of cations and electrons

Answer 38

Plasma