Can someone help me solve this question?
The gamma-ray photons emitted by the nuclear decay pf a technetium-99 atoms used in radoopharmaceuticals have an energy of 140.511 keV. Calculate the wavelength of these gamma rays.
1.23
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Re: 1.23
So 140.511 keV must be converted to J in order for us to use it. 1 keV is equal to 1.602x10^-16 J. Once you convert it you plug in that energy into E= hc/wavelength to find the wavelength.
Hope this helps!
Hope this helps!
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Re: 1.23
First, you would convert 140.511 keV to eV. 1 keV is 1000 eV, so you can do this by multiplying 140.511 X 1000 = 140.511 X 10^3 eV. Next, you would convert the energy from eV to Joules. 1 eV is 1.6022 x 10^-19 J, so you can convert the energy by multiplying 140.511 X 10^3 eV by 1.6022 X 10^-19 J/eV. This will give you an answer of 2.2513 X 10^-14 J. Now you can use the energy to calculate the wavelength. From using the equations E=hv and , you can write this equation to determine the wavelength: . Then, you would just plug in Planck's constant, the speed, and the energy you calculated to get the wavelength. I hope this helps!
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Re: 1.23
I know that we need to know some of the conversions and constants, but would we have to know that 1 eV is equal to 1.6022 x 10^-19 J for the test. Or would we just need to know how to use the number in the problem to get our answer and not memorize it.
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