Vibrational Spec

1. How many vibrations are there for CO₂? Show them all and indicate which are IR active and which are Raman active and explain how you know that.

2. How many vibrations are there for OH₂? Show them all and indicate which are IR active and which are Raman active and explain how you know that.

3. How many vibrations are there for HCN?

Show them all and indicate which are IR active and explain how you know that.

4. The carbonyl bond (C=O) in organic compounds absorbs at 1700 cm-1. Calculate the approximate force constant for bond making reasonable assumption about the reduced mass. Your answer should come out to be about 1200 N/m.

5. Interpret the major peaks in the following IR spectrum of acetic acid.

 6. DCl absorbs at 2095 /cm. What is the force constant for DCl?