Homework Problem 1.23


Moderators: Chem_Mod, Chem_Admin

Lauren Hekman 1A
Posts: 38
Joined: Fri Sep 25, 2015 3:00 am

Homework Problem 1.23

Postby Lauren Hekman 1A » Thu Oct 08, 2015 4:38 pm

The problem asks: "The gamma ray photons emitted by the nuclear decay of a technetium-99 atom used in radiopharmaceuticals have an energy of 140.511 keV. Calculate the wavelength of these gamma rays."

What is the unit keV? How do I convert this unit to joules?

Lauren Doh 3E
Posts: 13
Joined: Fri Sep 25, 2015 3:00 am

Re: Homework Problem 1.23

Postby Lauren Doh 3E » Thu Oct 08, 2015 4:44 pm

1 keV is equal to 1000 eV, and 1 eV is equal to 1.602x10^-19 Joules. So if you had 140.511 keV, you'd multiply it by 1000 eV / 1 keV. Then you'd multiply that by 1.602x10^-19 J / 1 eV.

Brooke Tobias 1B
Posts: 13
Joined: Fri Sep 25, 2015 3:00 am

Re: Homework Problem 1.23

Postby Brooke Tobias 1B » Fri Oct 09, 2015 10:13 am

Basically, an eV is the amount of energy transferred by an electron moved across an electric potential difference of one volt. This amount was derived from multiplying one volt (J/C) by the charge of a single electron (C), giving us 1.60218 x 10^-19 J.


Return to “Properties of Light”

Who is online

Users browsing this forum: No registered users and 1 guest