# Chemistry

The photoelectric work function of a metal is the minimum energy needed to eject an electron by irradiating the metal with light. For calcium, this work function equals 4.34 x 10-19 J. If light with a wavelength of 256 nm impinges on a piece of calcium, what is the speed of the ejected electron in m/s?
I was able to find the kinetic energy of the electron as 3.4x10^-19J but I can't figure out how to convert that to m/s

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1. K.E. = 1/2 m v^2

look up the mass of the electron (in kg), and solve for v

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posted by Scott

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