The flashcards below were created by user
on FreezingBlue Flashcards.
Frequency of absorption is measured in __ (___.
Wavelength units typically are __.
Frequency units are typically measured in __.
Mid-infrared frequency range is __.
- cm^-1 (wavenumbers)
- microns (10,ooo microns= 1cm)
- cm-1 (wavenumbers)
- 4000-400 cm-1
__ are higher than corresponding __ frequencies. (It is easier to __ a bond than to __ or __ it.)
Bonds to hydrogen have __ than those of heavier atoms.
Triple bonds have __ than corresponding double bonds, which in turn have __ than single bonds (except for bonds to hydrogen).
- stretching frequencies
- bending frequencies
- higher stretching freq. x3
Which has the higher frequency in terms of tetrahedral carbons?
sp> sp2> sp3
Infrared (IR) spectroscopy measures what?
Mass spectrometry __.
Nuclear magnetic resonance spectroscopy __.
UV spectroscopy uses __.
the bond vibration frequencies in a molecule and is used to determine the functional group.
fragments the molecule and measures the masses
- detects signals from hydrogen atoms and
- can be used to distinguish isomers
electron transitions to determine bonding patterns
Frequency and wavelength are __.
__, where c is the __.
Energy per photon= __, where h is __.
c= hv, where c is the speed of light
The IR Region
- Just below __ in the visible region.
- Wavelengths usually 2.5-25 um.
- More common units are __, the reciprocal of the __ in centimeters.
- __ are proportional to __ and __.
__ vibrate at only certain allowable frequencies.
Frequency decreases with __.
Frequency increases with __.
increasing atomic weight
increasing bond energy
__ with n atoms usually has __.
3n-6 fundamental vibrational modes
__ and __ are also quantitized.
No two molecules will give exactly the same __.
Whole-molecule vibrations and bending vibrations