IR Spectroscopy

Which of the following molecules will not show infrared spectrum?

• H2

• HCI

• CH4

• H20

What is the number of vibrational degrees of freedom in H2O?

• 2

• 3

• 4

• 1

What is the relation between wave number of IR absorption and the reduced mass?

• Wave number is directly proportional to reduced mass

• Wave number is inversely proportional to reduced mass

• Wave number is independent of the reduced mass

• Wave number is directly proportional to square of reduced mass

In which bending vibration, two atoms approach each other with respect to central atom

• Scissoring

• Rocking

• Wagging

• Twisting

In which bending vibration, two atoms move up and down the plane with respect to central atom

• Scissoring

• Rocking

• Wagging

• Twisting

What is the number of vibrational degrees of freedom in CO2?

• 2

• 4

• 6

• 3

What is the number of vibrational degrees of freedom in C6H6?

• 28

• 29

• 30

• 31

Which of the following range is incorrect

• near-IR, approximately 14000–4000 cm⁻¹

• mid-infrared, approximately 4000–400 cm⁻¹

• far-infrared, approximately 400–100cm⁻¹

• far-infrared, approximately 400–10 cm⁻¹

Tags

NGSS.HS-PS4-1

NGSS.HS-PS4-3

NGSS.HS-PS4-4

What is the range of finger prin region?

• 2000cm-1 to 1660cm-1

• 1500cm-1 to 400cm-1

• 2550cm-1 to 2000cm-1

• 3600cm-1 to 2870cm-1

Absorption band at 2100cm-1 to 2500cm-1 shows the presence of

• Double bond region

• Triple bond region

• Carbonyl functional group region

• Fingerprint region