IR Spectroscopy

A molecule absorbs IR at a wavenumber of 1720 cm^-1.  Which functional group could account for this absorption.
I. aldehydes
II. esters
III. ethers

• I only
• I and II 
• I, II and III 
• none of the above

Tags

NGSS.HS-PS4-3

Identify the bonds which will produce strong absorptions in the IR region of the electromagnetic spectrum.
I. C-O bond
II. C=C bond
III. C=O bond

• I and II only
• I and III only
• II and III only
• I, II and III

Tags

NGSS.HS-PS4-3

NGSS.HS-PS4-1

What part of the atom or molecule does infrared radiation affect

• the nucleus
• the electrons
• the  bonds
• the charge

Tags

NGSS.HS-PS4-3

The independent variable on an IR spectra is 

• wave length 
• wave number
• frequency squared
• transmission

Tags

NGSS.HS-PS4-1

The dependent variable on an IR spectra is 

• wave length 
• wave number
• frequency
• transmission

Tags

NGSS.HS-PS4-1

The greater the polarity of a bond the_______________its IR absorption

• weaker
• stronger
• more charged
• smaller the wavenumber

Non polar symmetrical molecules 

• do not absorb IR radiation
• absorb IR  radiation
• absorb the most IR  radiation
• transmit IR radiation

Tags

NGSS.HS-PS4-3

The finger print region is 

• different for each organic compound
•  from 600 - 1400 cm^-1
• both the above

Stronger bonds absorb  IR at 

• higher wave numbers
• lower wave numbers
• in the finger print region
• 600cm^-1

Tags

NGSS.HS-PS4-1

 Mass of attached atoms affect the absorbance of the bond

• True
• False