Question

Stronger bonds will be found where in the infrared spectrum?

a. higher molecular weight
b. lower wavenumbers
c. higher wavenumbers
d. lower molecular weight

Answer 1

Stronger bonds give infrared signals at c. higher wavenumbers.

Stronger bonds have higher vibrational energies.

E = hν = hc/λ

But ν̅ = 1/λ

∴ E = hcν̅

ν̅ increases as bond strength increases.