Question

What is the frequency of electromagnetic radiation needed to excite an electron in a hydrogen atom from the n = 3 orbit to the n = 6 orbit? How much energy does 800. millimoles of these photons have?

Answer 1

The energy of 800 milimoles of photons is 1.38 * 10^-19 J.

What is excitation of electrons?

We know that an electron can move from a lower to higher energy level according to the formula;

1/λ = RH(1/ni^2 - 1/nf^2)

RH = 1.097 * 10^7m-1

ni = 3

nf = 6

Thus;

1/λ = 1.097 * 10^7(1/3^2 - 1/6^2)

1/λ = 1.097 * 10^7(1/9 - 1/36)

1/λ = 1.097 * 10^7(0.11 - 0.03)

λ =1.14 * 10^-6 m

v = λf

f = v/λ

f = 3 * 10^8 m/s/1.14 * 10^-6 m

f = 2.6 * 10^14 Hz

Now

E = hf

E= 6.63 * 10^-34 * 2.6 * 10^14 Hz

E = 1.72 * 10^-19 J

Now;

1 mole of photons has 1.72 * 10^-19 J of energy

800 * 10^-3 moles of photons has 800 * 10^-3 moles * 1.72 * 10^-19 J/ 1 mole

= 1.38 * 10^-19 J

Learn more about energy of photons:brainly.com/question/2393994

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