Answer:
Explanation:
Energy of a orbital in hydrogen atom
En = [tex]-\frac{13.6 }{n^2} eV[/tex]
for n = 4
E₄ = [tex]-\frac{13.6 }{4^2} eV[/tex]
E₁ = [tex]-\frac{13.6 }{1^2} eV[/tex]
the energy of a photon emitted when an electron in a hydrogen atom undergoes a transition from n =4 to n =1.
E₄ - E₁ = [tex]( \frac{13.6 }{1^2} -\frac{13.6 }{4^2} )[/tex]
= 12.75 eV .