Calculate the wavelength of a photon in Angstrons having an energy of 1 electron-volt.

Answer

`12.40 xx 10^(3) Å`

Explanation

`E = 1 eV = 1.609 xx 10^(-19) J`
`E = hv = h (c)/(lamda)`
or `lamda = (hc)/(E) = ((6.62 xx 10^(34) Js) (3 xx 10^(8) ms^(-1)))/(1.602 xx 10^(-19) J) = 12.40 xx 10^(-7) m = 12.40 xx 10^(3) Å`