Video Transcript
An electron that is part of an atom
has greater energy than the minimum energy possible for electrons in that atom. Is the electron in an excited
state?
In this question, we are asked to
work out whether a particular electron in an atom is in an excited state. First, let’s recall that electrons
in an atom can occupy different energy levels. For example, let’s think about a
hydrogen atom, which only has one electron. The electron in this atom can
occupy one of many different energy levels.
We can represent these energy
levels using an energy level diagram, like this. This level right at the bottom
represents the minimum possible energy for the electron and is called the ground
state. Each of these higher-up levels
corresponds to a greater and greater energy, and these levels are called excited
states. Remember, too, that an electron’s
energy must correspond to a certain state. It’s not possible for an electron’s
energy to be in between levels.
In this question, we’re considering
an electron that has greater energy than the minimum possible energy, which tells us
that the electron is definitely not in the ground state. In order to be in the ground state,
an electron must have the minimum possible energy, which we know isn’t the case
here. And if an electron isn’t in the
ground state, it must occupy one of the higher energy states, or an excited
state.
So the answer to this question is
yes. The electron is in an excited
state.
