# Spectrophotometry and Beer-Lamberts Law

1. Nov 4, 2011

### joeyjo100

1. The problem statement, all variables and given/known data
A molecule has a spectral line at 27319 cm-1

what is its wavelength?
what is its frequency?

2. Relevant equations
A=εCl
where A=absorbance, ε=molar extinction coefficient, C=concentration and l=path length

3. The attempt at a solution
thought about doing 1 over the spectral line for the wavelength, and correcting the units, but then realised frequency is 1 over the wavelength, which would just be the original answer

If I'm honest, i am not sure what it means by a spectral line, think the question may be badly worded

2. Nov 4, 2011

### Ygggdrasil

Frequency is not 1/wavelength. It's easy to see that this equation is not true by looking at the units. Frequency has units of inverse time (e.g. s-1). Wavelength has units of distance (e.g. m). 1/wavelenght does not give units of inverse time.

Frequency is (speed of the wave)/wavelength. You can check the units to see that dividing a speed by a distance give units of inverse time.