chemical spectroscopy

Question 1

deals with the interaction of light with chemical substances

Answer 1

chemical spectroscopy

Question 2

only one part of the electromagnetic spectrum made of electromagnetic wave

Answer 2

light/visible light

Question 3

parts pf light

Answer 3

1. electric field component
   2, magnetic field component

Question 4

a disturbance that transmit energy

Answer 4

wave

Question 5

speed of light

Answer 5

3.0 × 10⁵ m/s

Question 6

speed of light =

Answer 6

wavelength × frequency

Question 7

wave energy =

Answer 7

planck’s constant × frequency

Question 8

electromagnetic spectrum (from lowest to highest)

Answer 8

1. radio waves
2. microwaves
3. infrared
4. visible light
5. ultraviolet
6. X-rays
7. Gamma rays

Question 9

type of quantum change in IR

Answer 9

change in configuration: bending, stretching, and scissoring

Question 10

type of quantum change in UV-VIS

Answer 10

change in electron configuration: molecular and atomic

Question 11

spectroscopic measurements

Answer 11

emission and absorption

Question 12

sample is exited by applying heat or electricity

Answer 12

emission

Question 13

when electrons return to ground state, they emit radiation characteristics of a given atom

Answer 13

emission

Question 14

measures the light absorbed as a function of wavelength

Answer 14

absorption

Question 15

components of various types of optical spectroscopy

Answer 15

1. source
2. wavelength selector
3. sample container
4. radiation detector
5. signal processing and read out unit

Question 16

isolates the desired wavelength band so that the only the band of interest is detected and measured

Answer 16

monochromator

Question 17

types of monochromator

Answer 17

1. grating
2. prism

Question 18

monochromator with 100-40,000 nm range

Answer 18

grating monochromator

Question 19

monochromator with 120-30,000 nm range

Answer 19

prism monochromator

Question 20

detector

Answer 20

phototubes

Question 21

works via photoelectric effect

Answer 21

phototubes

Question 22

UV-Vis spectrometer

Answer 22

source > monochromator >< shutter >< sample (blank) > detector> signal processor

Question 23

instrument components

Answer 23

1. source
2. monochromator (entrance slit, dispersion device, and exit slit)
3. sample
4. detector

Question 24

two ways of expressing amount of light

Answer 24

1. transmittance
2. absorbance

Question 25

human eye serves as the detector

Answer 25

colorimeter

Question 26

use a absorption or interference filters for wavelength selection and a photoelectric device for measuring radiant power

Answer 26

photometer

Question 27

uses a monochromator or a polychromator in conjunction with a transducer to convert the radiant intensities into electrical signals

Answer 27

spectrometers

Question 28

special type of spectrometer in which wavelength can be varied continuously, thus making scanning of absorption spectra possible

Answer 28

spectrophotometers

Question 29

one of the most useful techniques in investigating the structure of organic compounds

Answer 29

Infrared spectroscopy

Question 30

used as a tool for qualitative and quantitative determination of molecular species

Answer 30

infrared spectroscopy

Question 31

energy of IR photon insufficient to cause electronic excitation but can cause vibrational or rotational excitation

Answer 31

infrared absorption