UV Luminance Spectroscopy
For a molecule to absorb IR, why must the molecule's vibrations cause fluctuations in the dipole moment of the molecule?

Because a change in dipole moment lowers the energy required for electronic transitions
All of these
Because for absorption to occur, the radiation must interact with the electric field caused by changing dipole moment
Because fluctuations in the dipole moment allow the molecule to deform by bending and stretching

ANSWER DOWNLOAD EXAMIANS APP

UV Luminance Spectroscopy
In the intersystem crossing

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
a molecule converts its excess energy to light, and emits a photon
All of these

ANSWER DOWNLOAD EXAMIANS APP

UV Luminance Spectroscopy
Why phosphorescence measurements are usually made at a low temperature?

To increase the efficiency of the detector
To promote phosphorescence by slowing the rate of radiationless transfer processes
To prevent thermal degradation of the phosphorescent species
To decease the efficiency of detector

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
To allow for scattering by the sample
Because the magnitude of the output signal is proportional to the power of the incident radiation

ANSWER DOWNLOAD EXAMIANS APP