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Chemistry
Structure of Atom
the electron energy in hydrogen atom is given by e...

Question:
The electron energy in hydrogen atom is given by En = (–2.18 × 10^–18)/n² J. Calculate the energy required to remove an electron completely from the n = 2 orbit. What is the longest wavelength of light in cm that can be used to cause this transition?

Answer:

The expression for the energy of hydrogen of electron is

E_n = -2π²me⁴Z²/n²h²

Where m= mass of electrons

Z=atomic mass of atom

e = charge of electron

h = planck’s constant

When n = 1 then E_n = - (2.18X10^-18) (GIVEN)

When n = 2 then En= - (2.18X10^-18 )/4 = 0.5465X10^-18 J

Therefore the energy required for ionization from n = 2 is 5.45 x 10^-19 J

Now wavelength of light needed

= E=hv = hc/λ

λ = [{(6.62x10^-24)(3x10⁸)} / 5.45] x 10^-19 = 3647

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Question:
The electron energy in hydrogen atom is given by En = (–2.18 × 10^–18)/n² J. Calculate the energy required to remove an electron completely from the n = 2 orbit. What is the longest wavelength of light in cm that can be used to cause this transition?

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Question: The electron energy in hydrogen atom is given by En = (–2.18 × 10–18)/n2 J. Calculate the energy required to remove an electron completely from the n = 2 orbit. What is the longest wavelength of light in cm that can be used to cause this transition?

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Question:
The electron energy in hydrogen atom is given by En = (–2.18 × 10^–18)/n² J. Calculate the energy required to remove an electron completely from the n = 2 orbit. What is the longest wavelength of light in cm that can be used to cause this transition?