w2 terms (Atomic Structure & Spectroscopy, Molecular Spectroscopy & Chromatography)

Question 1

Absorption spectroscopy

Answer 1

Spectroscopic techniques that measure the absorption of radiation as a function of frequency or wavelength

Question 2

Bulk composition

Answer 2

What most of the object is made up of

Question 3

Electromagnetic radiation

Answer 3

A kind of radiation including visible light, radio waves, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously

Question 4

Element

Answer 4

A pure chemical substance consisting of a single type of atom distinguished by its atomic number

Question 5

Emission spectroscopy

Answer 5

Spectroscopic techniques that measure the electromagnetic radiation emitted when electrons drop from a higher energy level to a lower energy level

Question 6

Energy Dispersive X-ray Spectroscopy (EDX)

Answer 6

An analytical technique used for the elemental analysis or chemical characterization of a sample

Question 7

Energy level

Answer 7

The energy of a quantum state of a system

Question 8

Gamma ray

Answer 8

Electromagnetic radiation emitted from the nucleus of an atom by radioactive decay

Question 9

Neutron Activation Analysis (NAA)

Answer 9

An analytical method used to determine the chemical elements comprising a material by bombarding it with neutrons to produce radioactive atoms whose emissions are indicative of the elements present

Question 10

Part per billion (ppb)

Answer 10

1 in 1 000 000 000

Question 11

Part per million (ppm)

Answer 11

1 in 1 000 000

Question 12

Radioactive

Answer 12

Spontaneous emission of radiation, either directly from unstable atomic nuclei or as a consequence of a nuclear reaction

Question 13

Relative abundance

Answer 13

Amount of an element present in a given environment in comparison to all other elements

Question 14

Scanning Electron Microscope (SEM)

Answer 14

A type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons

Question 15

Trace impurities

Answer 15

What a very small portion of the object is made up of

Question 16

Chromatography

Answer 16

Method of separating a mixture into its components

Question 17

Compound

Answer 17

A pure chemical substance consisting of two or more different chemical elements

Question 18

Infrared (IR) spectroscopy

Answer 18

Analysis of infrared light interacting with a molecule

Question 19

Mass Spectrometry (MS)

Answer 19

An instrumental method for identifying the chemical constituent of a substance by means of the separation of gaseous ions according to their differing mass and charge

Question 20

Mobile phase

Answer 20

A fluid which carries a mixture through the stationary phase

Question 21

Molecule

Answer 21

Two or more atoms held together by chemical bonds

Question 22

Retention Factor (Rf)

Answer 22

A numerical method to describe the position of spots, i.e. the distance travelled by the compound divided by the distance travelled by the solvent

Question 23

Retention Time

Answer 23

The time taken for a solute to travel through the column

Question 24

Stationary phase

Answer 24

A layer fixed in place during the chromatography process and interacts with the analytes, e.g. silica layer in thin layer chromatography (TLC)