NEW
Font size
WorksheetsUV-Vis and Mass Spectroscopy Quiz
Total questions: 20
Worksheet time: 11mins
What is the main purpose of UV-Vis spectroscopy?
To measure the amount of light absorbed by a sample
To measure the amount of light transmitted through a sample
To measure the amount of light emitted by a sample
To measure the amount of light reflected by a sample
Which component of a UV-Vis spectrophotometer is responsible for selecting specific wavelengths of light for sample analysis?
Interference filter
Absorption filter
Monochromator
Cutoff filter
What is the relationship between absorbance (A) and transmittance (T) in UV-Vis spectroscopy?
A = 1/T
A = T
A = log(1/T)
A = log(T)
What is the main strength of UV-Vis spectroscopy as an analytical technique?
Limited applications
High cost of operation
Complex data analysis
Non-destructive nature
Which application of UV-Vis spectroscopy involves monitoring bacterial growth?
Beverage analysis
Pharmaceutical analysis
DNA and RNA analysis
Bacterial culture
Which component of a UV-Vis spectrophotometer may cause measurement errors due to a small amount of light from a wide wavelength range still being transmitted?
Interference from multiple absorbing species
Light scattering
Geometrical considerations
Stray light
In pharmaceutical analysis, how can UV-Vis spectroscopy be used to identify individual compounds in overlapping absorbance peaks?
By processing spectra using mathematical derivatives
By increasing the concentration of the compounds
By changing the light source
By using a different type of cuvette
All electromagnetic waves travel at the speed of light.
True
False
When a molecule absorbs energy in the UV or Visible region
-------------------- transition takes place?
Vibrational
Rotational
Electronic
Vibrational-rotational
Which transition requires low energy?
sigma to sigma *
pi to pi*
n to sigma*
n to pi*
UV spectrum is a plot of ------------ versus absorption intensity
frequency
wavelength
wavenumber
energy
The amount of light that passes through a sample is called:
Transmittance
Radiation
Absorbance
Wavelength
_____________________unsaturated organic functional groups that absorb in the UV-VIS
Azeotropes
Chromosomes
Chromophore
Carbonyl
What is the relationship between absorbance and concentration in UV-Vis spectroscopy?
Directly proportional
Inversely proportional
No relationship
Exponential relationship
Which type of molecules are most likely to exhibit strong absorption in the UV region?
Non-polar molecules
Polar molecules
Aromatic molecules
Aliphatic molecules
What is the purpose of using a reference cuvette in UV-Vis spectroscopy?
To calibrate the instrument
To measure the absorbance of the sample
To adjust the wavelength range
To increase the sensitivity of the detector
What do the peaks on the mass spectrum represent?
anions
mass of positively charged fragments
mass of negatively charged fragments
numbers of electrons
The above Mass Spectra of an unknown substance contains an M+ peak of 64 and an M+2 Peak. What is the molecular weight of this substance?
29
49
64
66
The above Mass Spectra of an unknown substance contains an M+ peak of 64 and an M+2 Peak. Which of the following could be the formula for this substance?
CH3CH2Cl
CH3CH2CH2NH2
CH3CH2Br
CH3CH2N2
Which of the following molecular formulas could correspond to the above mass spectrum?
C6H5Br
C6H5Cl
C6H5CH2Br
C6H5CH2Cl
