Final answer:
An atom in an excited state has more potential energy than in its ground state due to electrons absorbing energy and moving to higher energy levels.
Step-by-step explanation:
An atom in an excited state contains more potential energy than the same atom in the ground state. This higher energy level is a result of the electron absorbing energy and moving to a higher energy orbit, making the atom less stable. The excited state of the atom has more energy because its electrons have absorbed energy to move to a higher energy level, but this state is temporary. When the electron returns to the ground state, it emits a photon, thereby releasing the previously absorbed energy.