Question

(1)

Part A: If a electron in a hydrogen atom makes a transition from ground state to n = 8 level what wavelength of light in (nm) would be needed for the abosorbed photon to cause the transition?

Part B: If the same electron falls to a lower level by emmitting a photon of light in the Paschen series what is the frequncy of light in (Hz) thats emitted?

(2) When a photon have a wavelength of 195nm strikes the surface of gold metal it ejects an electron with a kinetic energy of 1.25 ev. what are the binding energy of the metal and largest wavelength of light that's capable of ejecting electron nfroma gold surface?

Answer 1

part A

(1/wavelength) = 109677(1/n1^-1/n2^2)

(1/x) = 109677((1/1^2)-(1/8^2))

x = 9.26*10^(-6) cm

=   9.26*10^(-8) m

part B

Paschen series

n1 = 3 , n2 = 8

wave number= = 109677(1/n1^-1/n2^2)

         = 109677((1/3^2)-(1/8^2))

         = 10472.63 cm-1

frequency = c*wave number

         = 3*10^10*10472.63

       = 3.141789*10^14 hz