# chem

posted by on .

The mass of an electron is 9.11\times 10^{-31}~\rm kg. If the de Broglie wavelength for an electron in a hydrogen atom is 3.31\times 10^{-10}~\rm m, how fast is the electron moving relative to the speed of light? The speed of light is 3.00\times10^8 ~\rm m/s.

• chem - ,

w = wavelength
w = h/mv with m in kg.
Solve for velocity in m/s.
Then v/3E8 = velocity relative to c.