Calculate the energy of an electron in the n = 2 level of a hydrogen atom.

Question

Energy =  ?? Joules

Answer 1

For the hydrogen atom, which has 1 electron, you can use the Bohr model and this equation

E(n) = - (1/n²) * 13.6 eV

In this equation, the Energy, E, is a function of the energy level, n. The units for the energy are in eV, which will have to be converted.

For n=2, we have E(2) = - (1/2²) * 13.6 eV

E(2) = -(1/4) * 13.6 eV

E(2) = -3.40 eV

We can convert using 1 eV = 1.602 x10^-19 J

So -3.40 eV * 1.602 x10^-19 J / 1 eV = -5.45 x10^-19 J

Note that the energy is negative. As you go to higher values of n, the energy will be less negative. This is the energy that would have to be absorbed by the electron to remove the electron from the atom.