7. Infrared Spectroscopy Flashcards
1
Q
What does IR spectroscopy show?
A
The bending and stretching (vibrations) of covalent bonds.
2
Q
How are the bonds picked up?
A
They absorb energy in the IR region of the electromagnetic spectrum, and the wavelength absorbed depends on the bond.
3
Q
What runs along the horizontal axis of an IR spectrum?
A
Wavenumber (cm-1️⃣)
1 divided by the wavelength in cm
4
Q
How far does the horizontal axis run?
A
Left to right, 4000cm-1️⃣ to 400cm-1️⃣
5
Q
What runs along the vertical axis of an IR spectrum?
A
% transmittance, so the graph shows dips down from 100%
6
Q
How are the peaks significant?
A
They indicate the presence of a particular bond or functional group
7
Q
What is the fingerprint region?
A
Between 500 and 1300cm-1️⃣. It is specific to any particular molecule.
