Answer to Question #171477 in General Chemistry for Dawson

Question

Covalent bonds in a molecule absorb radiation in the IR region and vibrate at characteristic frequencies.

(a) A molecular vibration absorbs radiation of wavelength 25.5 μm. What frequency (in s⁻¹) corresponds to that wavelength? Enter your answer in scientific notation.

(b) A molecular vibration has a frequency of vibration of 7.182 × 10¹³ Hz. What wavelength (in μm) corresponds to that frequency? Do not answer in scientific notation.

Answer 1

1. Let π be lamda

c= 3 x10⁸

f = c/π

= 3 x10⁸ / 25.5 x 10 ^-6

= 11.76 x10¹³Hz

2. π = c/f

= 3 x10⁸ m/s /7.182 × 10¹³ Hz

= 4.20 x 10^-6

= 4.2μm