Spectroscopy Flashcards
Higher energy means (higher/lower)frequency and (longer/shorter) wavelength.
Higher frequency, shorter wavelength
Lower energy means (higher/lower) frequency and (longer/shorter) wavelength.
Lower frequency, longer wavelength
What is the wavelength range of the IR region of the electromagnetic spectrum?
2.5-25 micrometers
Wavenumbers are proportional to…
Frequency and energy
Frequency (increases/decreases) with increasing atomic mass
Decreases
Frequency (increases/decreases) with bond energy
Increases
(Polar/Nonpolar) bonds are usually IR-active
Polar
Bonds with more s character absorb at a (higher/lower) frequency
Higher
Secondary amine signal is…
Broad with 1 sharp spike
Primary amine signal is…
Broad with 2 sharp spikes (think 1 per hydrogen)
Tertiary amine signal is…
No signal for tertiary amine
Aldehydes have two C-H signals around…
2700-2800 cm-1
In NMR, the number of signals shows…
How many different kinds of protons are present
In NMR, the location of the signals shows…
How shielded or deshielded the proton is
In NMR, the intensity of the signal shows…
The number of protons of that type
In NMR, signal splitting shows…
The number of protons on adjacent carbon atoms
What compound is the internal standard for NMR with a signal of 0 ppm?
TMS (tetramethylsilane)
Aldehydes show up on NMR at…
9.5-10.5
Aromatic hydrogens show up at…
6.5-8.5
Carboxylic acid protons show up at…
10+
Phenol shows up at…
4-7
Esters show up at…
3.5-4.5
Ethers show up at…
3-4
Ethyl groups have a splitting pattern of….
Quartet/triplet
Isopropyl groups have a splitting pattern of…
Septet/doublet
Degrees of unsaturation formula
(2C - H - X + N + 2)/2
