Spectrophotometer

Question 1

These are instruments that measure light energy. Examples are spectrophotometers, FEP, AAS

Answer 1

Optical Instruments

Question 2

Kind of light at 400-700nm

Answer 2

Visible spectrum

Question 3

Less than 400nm

Answer 3

UV

Question 4

Greater than 700nm

Answer 4

IR

Question 6

This energy transmitted via electromagnetic waves characterized by frequency and wavelength

Answer 6

Ligh Energy

Question 7

Wavelength is ________ proportional to energy

Answer 7

Inversely Proportional

Question 8

What do you use to check wavelength accuracy?

Answer 8

Didymium / Holmium Oxide Filter

Question 9

Order of wavelength in Visible Light

Answer 9

“VIBGYOR” 400 to 700 nm
Red = High WL, Low Energy
Violet = Low WL, High Energy

Question 10

Spectrophotometer: Concentration of substance is _____ to the amount of light absorbed and _____ to the log of transmitted light.

Answer 10

Spectrophotometer: Concentration of substance is DIRECTLY PROP to the amount of light absorbed and INDIRECTLY PROP to the log of transmitted light.

Question 11

This prevents stray light

Answer 11

Entrance Slit

Question 12

Type of light source that emits radiation that changes in intensity

Answer 12

Continuum Source

Question 13

Type of light source that has limited radiation and wavelength

Answer 13

Line Source

Question 14

Indicate IR light sources

Answer 14

Merst-Glower
Globar

Question 15

Indicate VIS/IR light source

Answer 15

Tungsten-Halogen Lamp

Question 16

Indicate UV light sources

Answer 16

Mercury Arc Lamp
Deuterium Discharge
Xenon Arc Lamp
Hydrogen Lamp

Question 17

This is the most common cause of loss of linearity, dispersion of second-order spectra

Answer 17

Stray Light

Question 18

This controls the width of light beam /bandpass

Answer 18

Exit Slit

Question 19

This part of the spectrophotometer isolates the wavelength

Answer 19

Monochromator

Question 20

Type of monochromator with purest UV

Answer 20

Prisms

Question 21

Most sensitive and most common monochromator

Answer 21

Fraction Gratings

Question 22

Least expensive mmonochromator

Answer 22

Colored glass filters

Question 23

Indicate all examples of monochromators

Answer 23

Prisms
Fraction Gratings
Interference filters
Colored Glass Filters

Question 24

This part of the spectrophotometer converts transmitted light to electrical energy for easier measure than light

Answer 24

Photodetectors

Question 25

This is an internal current photodetector

Answer 25

Barrier-Layer Cell / Photocell / Photovoltage

Question 26

Most Sensitive and most common photodetector; DYNODES

Answer 26

Photomultiplier

Question 27

External and multichannel photodetector

Answer 27

PhotodiodeCa

Question 28

Cathode Anode Photodetector

Answer 28

Phototube

Question 29

Factors for choosing a light source:

Answer 29

Range, Spectral, Source, Stability, Temp

Question 30

Most common type of sample holder/cuvette used and why

Answer 30

Square-end. Path length needs to be the same, easier to do for square

Question 31

Most common example of cuvette

Answer 31

Alumina SIlica Glass

Question 32

Enumerate all examples of cuvettes

Answer 32

Alumina-Silica Glass
Quartz-Plastic (for UV)
Borosilicate Glass
Soft Glass