EXperiment 1: IR
Calculate the reduced mass for C-H bond?
0.92
What is the amide C=O stretch?
1600-1670cm^-1 it is skinny
What is the C=O stretch?
1650-1800cm^-1 broad
What are the weak characteristic vibrational overtones for aromatic rings (3-4 signals)?
1665-2000cm^-1
What is the alkyne C triple bond C stretch?
2100-2300cm^-1 weak, medium, sharp
What is the nitrile C triple bond N stretch?
2200-2300cm^-1 weak, medium, sharp
What is the carboxylic acid stretch?
2400-3400cm^-1 O-H very board
What is the alkyl C-H stretch?
2850-2000cm^-1
what is the C-H stretch?
2850-3150cm^-1 weak, medium sharp stretch
What is the alkene/arene C-H stretches?
3000-3150cm^-1
What is the N-H stretch?
3100-3500cm^-1 weak,sharp
What is the O-H stretch?
3200-3400cm^-1 strong, board
What is the alkyne C-H stretch?
3300cm^-1 medium, strong, sharp
What is the fingerprint region?
400-1400cm^-1
Calculate the reduced mass for a C-C bond.
6.0
What are the aromatic C-H bends?
650-900cm^-1
Based on the reduced mass of C-H and C-C, which bond exhibits a higher frequency of vibration?
C-H bond
Which of the following statements about spectroscopy are false? a) spectroscopy is used to gather information about chemical structure b)all spectroscopies require IR radiation c)IR spectroscopy examines the interaction of infrared radiation with matter d)NMR spectroscopy examines the interaction of radio waves with matter e) IR spectroscopy can be used to determine what functional groups are present in molecules
b)all spectroscopies require IR radiation
In the IR spectrum of acetone, which of the following signals fall in the fingerprint region? a)3005 wavenumbers b)2699 wavenumbers c)3005cm^-1 d)1715cm^-1 e)1360cm^-1 f)1211 wavenumbers
e)1360cm^-1 f)1211 wavenumbers
Which fall into the bending category?
scissoring, rocking, wagging, and twisting
What are vibrations categorized into?
stretching and bending modes
Based on Hookes law what is the relationship between frequency and reduced mass?
they are inversely proportional
