VIBRATIONAL SPECTROSCOPY

Question 1

Vibrational spectroscopy involves the transitions falling in the spectral range of ____________
a) 100-1000 cm-1
b) 300-3000 cm-1
c) 400-4000 cm-1
d) 500-5000 cm-1

Answer 1

c) 400-4000 cm-1

Question 2

Which of the region of IR spectra appears between (1400-600) cm-1?
a) Functional group region
b) Fingerprint region
c) Low-frequency region
d) None of the mentioned

Answer 2

b) Fingerprint region

Question 3

Select the correct statement from the following option.
a) Infrared spectra can identify the unknown materials
b) It can determine the amount of components in a mixture
c) It can also determine the quality of a sample
d) All of the mentioned

Answer 3

d) All of the mentioned

Question 4

Which of the following molecule have infrared active vibrations?
a) NO
b) CH4
c) H2
d) All of the mentioned

Answer 4

a) NO

Question 5

Which of the following cannot show a vibrational absorption spectrum?
a) OCS
b) H2O
c) CO2
d) C H2 = C H2

Answer 5

d) C H2 = C H2

Question 6

Which of the following is not a type of bending molecular vibration?
a) Twisting
b) Stretching
c) Wagging
d) Rocking

Answer 6

b) Stretching

Question 7

What is the absorption frequency(cm-1) of –C=N functional group?
a) 3610-3640
b) 1690-1760
c) 1180-1360
d) 2850-2960

Answer 7

c) 1180-1360

Question 8

Presence of a functional group in a compound can be established by using _____________
a) Chromatography
b) IR spectroscopy
c) Mass spectroscopy
d) X-ray diffraction

Answer 8

b) IR spectroscopy

Question 9

Select the incorrect option from the following option.
a) IR spectroscopy helps in the determination of purity
b) IR spectroscopy helps in the determination of force constant from vibrational spectrum
c) IR spectroscopy helps in identifying an unknown compound
d) None of the mentioned

Answer 9

d) None of the mentioned

Question 10

IR spectroscopy helps in detecting the presence of hydrogen bonding.
a) True
b) False

Answer 10

a) True