# Question #3b6cf

Jan 11, 2017

The Bohr model does apply to $\text{He"^"+}$. It does not apply to $\text{H"^"+", "Li"^"+}$, or $\text{Be"^"2+}$.

#### Explanation:

The Bohr model applies only to a hydrogen atom or to ions that contain only one electron (hydrogen-like ions).

To get a hydrogen-like ion, we must remove all but one of the electrons from an atom.

Such ions include $\text{He"^"+", "Li"^"2+", "Be"^"3+}$, etc.

They do not include $\text{H"^"+}$ (no electron) or $\text{Li"^"+}$ and $\text{Be"^"2+}$ (two electrons each).

Why doesn't the model work for multi-electron atoms?

If the species had two electrons, the mathematical calculations would have to include a term representing the repulsions between the electrons.

This makes the equations extremely difficult to solve, and they are next to impossible with three or more electrons.

Thus, we cannot apply the equations of the Bohr model to any other atom.