Consider the following energy levels of a hypothetical atom: E 4 -1.21 x 10 -19
ID: 1003167 • Letter: C
Question
Consider the following energy levels of a hypothetical atom:
E4 -1.21 x 10 -19 J
E3 -5.61 x 10 -19 J
E2 -1.25 x 10 -18 J
E1 -1.45 x 10 -18 J
(Part A) What is the wavelength of the photon neeed to excite an electron from E1 to E4?
(Part B) What is the energy(in joules) a photon must have in order to excite an electron from E2 to E3?
(Part C) When an electron drops from the E3 level to the E1 level, the atom is said to undergo emission. Calculate the waelength of the photon emitted in this process.
Please put answers into scientific notation
Explanation / Answer
1)E1 to E4
delta E = (-1.21*10^-19)-(-1.45*10^-18) = 1.329*10^-18 J
WE KNOW , E = hc/lamda .....lamda = wavelength ,
h = plancks constant , c = speed of light.
=> wavelength = hc/(delta E)
wavelength = 1.49*10^-7 metres.
2)
delta E = E3-E2 = (-5.61*10^-19)-(-1.25*10^-18) = 6.89*10^-19 J
3)
delta E = (-5.61*10^-19)-(-1.45*10^-18) = 8.89 *10^-19 J
wavelength = hc/(delta E) = 2.23*10^-7 metres.