HOMEWORK WITH CHEMISTRY

Question

Calculate the energy of a photon of electromagnetic radiation at each of the following wavelengths.
Part A
488.0 nm (wavelength of argon laser)

Part B
12.24 cm (wavelength of microwave oven)

Part C
0.0520 nm (a wavelength contained in medical X-rays)

Answer 1

These are all answered the same way.  I will do the first one for you, and then you work the others the same way.

 

(A)

 

E = hc/λ 

 

E = photon energy

h = Planck's constant = 6.626 × 10⁻³⁴ Js

c = speed of light = 3 x 10⁸ m/s

λ = wavelength = 488.0 x 10^-9 m

 

E = (6.626 × 10⁻³⁴)(3 x 10⁸) / (488.0 x 10^-9) J ≅ 4.073 x 10^-19 J

 

Now you work the others.  Just replace the wavelength in the equation, and be careful with units.