Question

The most convenient spectroscopic technique to establish the presence of intermolecular hydrogen bonding is:

• A. UV
• B. IR
• C. NMR
• D. None of the above

Hint:

Think about which technique directly measures bond stretching frequencies.

Answer 1

The Correct Option is B

H-bonding weakens X-H bond (smaller k), lowering vibrational frequency (O-H shifts from ~3600 to 3200-3400 cm-1). This lies in IR region, directly measured by IR spectroscopy.

\[\boxed{\text{IR}}\]