# 5 Quantum energy levels

You probably won’t be surprised to know that there is an equation for energy levels! Equation 2 is used to calculate the energy of a certain level (*E _{n}*) when you know the energy level (

*n*). This

*n*can take any integer value, that is 1, 2, etc.

You should note the minus sign. It means that the electron is bound to an atom. You need to give it this amount of energy to release it. You can practise calculating energy levels in Activity 7.

## Activity 7 Calculating energy values

a.

–1.51 eV

b.

–3.4 eV

c.

–13.6 eV

d.

–27.2 eV

e.

13.6 eV

The correct answer is c.

a.

–1.51 eV

b.

–3.4 eV

c.

–13.6 eV

d.

–27.2 eV

e.

13.6 eV

The correct answer is b.

a.

–1.51 eV

b.

–3.4 eV

c.

–13.6 eV

d.

–27.2 eV

e.

13.6 eV

The correct answer is a.

You will now look at probably the most famous experiment in physics: the double slit experiment.