Problem 1.55 part A

$c=\lambda v$

Katherine Jordak 1H
Posts: 51
Joined: Fri Sep 29, 2017 7:05 am

Problem 1.55 part A

Part A: If an absorption occurs in the infrared spectrum at 3600 cm^-1, what is the frequency of radiation that corresponds to that absorption?

When I did this problem I used the equation
wavelength x frequency = c

I converted 3600 cm^-1 into meters before plugging it into the problem and got 1.1 x 10^10 Hz for the frequency. However, in the solutions manual, the wavelength was kept in cm and c was changed to 2.99792 x 10^10 cm•s^-1. They got 1.1 x 10^14 Hz as the frequency.

I can't seem to figure out how, by converting the wavelength into meters, my answer is 4 decimal places off.

Eli Aminpour 2K
Posts: 50
Joined: Fri Sep 29, 2017 7:04 am

Re: Problem 1.55 part A

the method you used to solve the problem works too, the problem is difficult because concerting cm^-1 to m^-1 is tricky. you have to multiply the 3600 cm^-1 by (100 cm/1 m) so that the centimeters cancel and you are left with meters in the denominator. This should give you the answer in the solution manual.