MMSC 407 CLINICAL CHEMISTRY FINAL
EXAM SCRIPT 2026 COMPREHENSIVE
QUESTIONS AND ANSWERS VERIFIED A+
●● what is the order of the basic components of a spectrophotometer
Answer: 1. light source
2. collimating lens
3. entrance slit
4. monochromator
5. exit slit
6. sample cuvette
7. PM tube
8. photodetector
9.display
●● Types of light sources Answer: Tungsten (quartz vapor): visible light
Hydrogen/deuterium: UV light
Xenon/mercury vapor: UV light
●● considerations for light source Answer: cool constant beam of light
intense light with small filament
easily replaceable, highly reproducible
,●● what is a collimating lens? Answer: curved optical lens that make the
light rays parallel
●● what is the purpose of a monochromator? Answer: selects a narrow
range of wavelengths from the white light
●● visible light wavelengths Answer: · 350-430 violet
· 430-475 blue
· 475-495 blue-green
· 495-505 green-blue
· 505-555 green
· 555-575 yellow green
· 575-600 yellow
· 600-650 orange
. 670-700 red
· Below 350 : UV
●● What is a bandpass? Answer: the actual range of wavelengths
transmitted by a monochromator.
each instrument will have a different bandpass
●● Bandpass are influenced by Answer: Type of monochromator
,Exit slit width
Distance between the monochromator and exit slit (greater the distance
the more narrow the bandpass)
●● Interference filter Answer: composed of 2 parallel sheets of half-
silvered glass surrounding a core of MgF2
ADV: good bandpass
DISADV: dirty easily, one filter per wavelength
●● prism Answer: ADV: narrow bandpass, spectrum of wavelengths
DISADV: expensive
●● diffraction grating Answer: Composed of polished reflective surfaces
onto which sharply defined, parallel grooves have been etched
ADV: narrow bandpass
DISADV: expensive
●● Properties of types of cuvettes Answer: shape: round or sqaure
(square is better because it relfects less light)
Type of material
clear glass
quartz: UV
plastic: most common
, flow: through the cuvette
●● What is a photomutiplier tube? Answer: amplifies the primary signal
best and most senstive photodetector
●● wavelength calibration Answer: Preformed daily
Purpose: to ensure that the wavelength indicated on the wavelength dial
is the actual wavelength of the light passed by the monochromator
didymium filter
●● Absorbance calibration/photometric accuracy Answer: Preformed
daily
Purpose: ensures the absorbance reading is accurate and linear
To ensure a lack of stray light
Neutral density filter (340 nm , 500 nm) and cobalt ammonium sulfate
solutions
●● Temperature impact on spectrophotometry Answer: The amount of
light emitted at each wavelength depends upon the temperature of the
filament
Temperature fluctuations can cause changes in the spectrum of light
Must allow spec to warm up before use
EXAM SCRIPT 2026 COMPREHENSIVE
QUESTIONS AND ANSWERS VERIFIED A+
●● what is the order of the basic components of a spectrophotometer
Answer: 1. light source
2. collimating lens
3. entrance slit
4. monochromator
5. exit slit
6. sample cuvette
7. PM tube
8. photodetector
9.display
●● Types of light sources Answer: Tungsten (quartz vapor): visible light
Hydrogen/deuterium: UV light
Xenon/mercury vapor: UV light
●● considerations for light source Answer: cool constant beam of light
intense light with small filament
easily replaceable, highly reproducible
,●● what is a collimating lens? Answer: curved optical lens that make the
light rays parallel
●● what is the purpose of a monochromator? Answer: selects a narrow
range of wavelengths from the white light
●● visible light wavelengths Answer: · 350-430 violet
· 430-475 blue
· 475-495 blue-green
· 495-505 green-blue
· 505-555 green
· 555-575 yellow green
· 575-600 yellow
· 600-650 orange
. 670-700 red
· Below 350 : UV
●● What is a bandpass? Answer: the actual range of wavelengths
transmitted by a monochromator.
each instrument will have a different bandpass
●● Bandpass are influenced by Answer: Type of monochromator
,Exit slit width
Distance between the monochromator and exit slit (greater the distance
the more narrow the bandpass)
●● Interference filter Answer: composed of 2 parallel sheets of half-
silvered glass surrounding a core of MgF2
ADV: good bandpass
DISADV: dirty easily, one filter per wavelength
●● prism Answer: ADV: narrow bandpass, spectrum of wavelengths
DISADV: expensive
●● diffraction grating Answer: Composed of polished reflective surfaces
onto which sharply defined, parallel grooves have been etched
ADV: narrow bandpass
DISADV: expensive
●● Properties of types of cuvettes Answer: shape: round or sqaure
(square is better because it relfects less light)
Type of material
clear glass
quartz: UV
plastic: most common
, flow: through the cuvette
●● What is a photomutiplier tube? Answer: amplifies the primary signal
best and most senstive photodetector
●● wavelength calibration Answer: Preformed daily
Purpose: to ensure that the wavelength indicated on the wavelength dial
is the actual wavelength of the light passed by the monochromator
didymium filter
●● Absorbance calibration/photometric accuracy Answer: Preformed
daily
Purpose: ensures the absorbance reading is accurate and linear
To ensure a lack of stray light
Neutral density filter (340 nm , 500 nm) and cobalt ammonium sulfate
solutions
●● Temperature impact on spectrophotometry Answer: The amount of
light emitted at each wavelength depends upon the temperature of the
filament
Temperature fluctuations can cause changes in the spectrum of light
Must allow spec to warm up before use
