# Homework Help: About The Bohr Model of the Hydrogen Atom

1. Jun 24, 2010

### A B C

1. The problem statement, all variables and given/known data

What energy (in eV) is required to remove the remaining electron from a singly ionized helium
atom, He+ (Z = 2)?
(a) 3.40 eV (c) 27.2 eV (e) 76.9 eV
(b) 13.6 eV (d) 54.4 eV

2. Relevant equations

Ei - Ef = hf

3. The attempt at a solution

Ef: the 1st level
Ei: the 2nd level

2. Jun 24, 2010

### graphene

Do you know the relation between E and Z & n.

$$E \propto Z$$
$$E \propto \frac{1}{{n}^{2}}$$

For the ground state(n=1) of hydrogen(Z=1), E = -13.6eV

Here Z=2 & n=1.

Last edited: Jun 25, 2010
3. Jun 24, 2010

### A B C

Thanks a lot (: