# Energy Of Electrons

Submitted by antgoblue on Sat, 10/27/2007 - 20:40

The energy (in joules) of an electron energy level in the Bohr atom is given by the expression: En = -2.179E-18/n2 J where n is the quantum number that specifies the energy level. What is the frequency in Hz of the radiation emitted when an electron falls from level n = 2 to level n = 1?

Thanks for all you do

Some thoughts for you as you work to solve this.
Can you determine the energy associated with the two quantum levels?
so, what is the energy difference of the two?
What is the relationship equating energy to frequency?

ok so its -2.179 x10^-18 /2^2 and -2.179x10^-18/1^2 subtract those #'s from each other and then multply that by Planks Constant ( 6.626 X 10^-34)

That will get my answer right?

2 general rules to follow in problem solving, especially in chemistry, are

You'll find the problem in determining the frequency, Energy is directly proportional to Plank's constant times frequency.

So is the problem like this

(-2.179x10^-18)/2^2= (-5.448x10^-19)

(-2.179x10^-18)/1^2= (-2.179x10^-18)
then you subract these two #'s
(-5.448x10^-19)- (-2.179x10^-18)to get (1.6342x10^-18)

then you plug this into the equation freq= ener* planks constant so its
(1.6342x10^-18)  X  (6.626x10^-34)
to get a final answer of (1.083x10^-51) Is my work right??

If Energy = Planck's constant x frequency

frequency =          Energy
Planck's Constance