Final answer:
The lowest energy level higher than the ground state in an atom is known as the excited state. An electron absorbs a photon to reach this state and emits a photon when returning to the ground state.
Step-by-step explanation:
The lowest energy level that is higher in energy than the ground state is referred to as the excited state. When an electron in an atom absorbs a photon, it gains energy and may jump from the ground state to an excited state. The electron, now at a higher quantized energy level, eventually transitions back to the ground state, releasing a photon in the process. The amount of energy of the photon corresponds to the difference between the excited and ground state energy levels. This process is a fundamental concept in quantum mechanics and is essential in the understanding of atomic and molecular behavior.