(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The first five ionization energies of hydrogen are 1312, 328, 146, 82 and 52 kJ/mol. Calculate the wawelength of the first three in Balmer series.

2. Relevant equations

Avokadro constant, N_{A}= 6,022 x 10^{23}/mol

Planck constant, h = 6,626 x 10^{-34}Js

speed of light, c = 2,998 x 10^{8}ms^{-1}

energy, E in J

wavelength, lambda in nm = 10^{-9}m

frequency of radiation, v in s^{-1}

E = hv

c = lambda x v

3. The attempt at a solution

So, in my knowledge you only need the first three energies given in problem and the energies represents the value of one mole of photons. So dividing the 1312 with Avokadro you will get the energy of one photon which is 2.17868 x 10^{-21}J

Using the equation E = hv you will get v = 3,28807 x 10^{12}s^{-1}

and using c = lambda x v you will get lambda = 9,1178 x 10^{-5}nm

So the exponent is definitely wrong but so are numbers because this wavelength should be visible to human eye (400-780nm). You can solve this other way when you are not using the given energies and the rydberg value is present in the equation but this should be another way to do this.

Thx beforehand

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# Homework Help: Basic quantum physics, Balmer series

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