UV Luminance Spectroscopy
Why do fluorescence spectrometers often use double-beam optics?

To compensate for beam attenuation by the monochromator
To compensate for power fluctuations in the radiation source
All of these
So a reference solution can be used

ANSWER DOWNLOAD EXAMIANS APP

UV Luminance Spectroscopy
In the intersystem crossing

All of these
a molecule converts its excess energy to light, and emits a photon
the spin of an excited electron reverses, changing the state of the molecule (from singlet state to triplet state or vice versa)
a molecule converts excess electronic energy to vibrational energy

ANSWER DOWNLOAD EXAMIANS APP

UV Luminance Spectroscopy
Fluorescence occurs when

a molecule returns to the electronic ground state from an excited triplet state by losing it's excess energy as a photon
None of these
a molecule returns to the electronic ground state from an excited singlet state by losing it's excess energy as a photon
a molecule lowers its vibrational energy by losing it's excess energy as a photon

ANSWER DOWNLOAD EXAMIANS APP

UV Luminance Spectroscopy
Why must the radiation source for fluorescence spectrometry be more powerful than for absorption spectroscopy?

Because the sample won't fluoresce if the incident radiation is of low power
None of these
Because the magnitude of the output signal is proportional to the power of the incident radiation
To allow for scattering by the sample

ANSWER DOWNLOAD EXAMIANS APP

UV Luminance Spectroscopy
Internal conversion is where

A molecule converts excess electronic energy to vibrational energy
A molecule converts its excess energy to light, and emits a photon
the spin of an excited electron reverses, changing the state of the molecule (from singlet state to triplet state or vice versa)
None of these

ANSWER DOWNLOAD EXAMIANS APP