Excited State

Definition

An excited state is a higher energy state of an atom or molecule compared to its ground state. In this state, an electron has been promoted to a higher energy level, storing potential energy that can be released through various processes.

5 Must Know Facts For Your Next Test

1. Excited states are created when an atom or molecule absorbs energy, typically in the form of light or heat, which promotes an electron to a higher energy level.
2. The energy difference between the excited state and the ground state determines the wavelength of the photon that will be emitted when the electron returns to the ground state.
3. Excited states are unstable and the electron will eventually return to the ground state, releasing the stored energy as a photon or through other relaxation processes.
4. The quantization of energy levels in atoms and molecules is a fundamental concept that explains the discrete nature of excited states and the emission of specific wavelengths of light.
5. The study of excited states and the transitions between energy levels is crucial for understanding the behavior of atoms and molecules, as well as the properties of electromagnetic radiation.

Review Questions

• Explain how the concept of excited states is related to the quantization of energy in atoms and molecules.
  • The quantization of energy levels in atoms and molecules means that electrons can only occupy discrete, specific energy levels. When an atom or molecule absorbs energy, an electron can be promoted to a higher energy level, creating an excited state. This excited state is unstable, and the electron will eventually return to the ground state by emitting a photon with an energy equal to the difference between the excited state and the ground state. The quantization of energy levels is a fundamental principle that explains the discrete nature of excited states and the specific wavelengths of light emitted during the transition between energy levels.
• Describe the relationship between excited states and the properties of the electromagnetic spectrum.
  • The energy differences between excited states and the ground state of atoms and molecules determine the wavelengths of light that can be absorbed and emitted. When an electron in an atom or molecule is excited to a higher energy level, it stores potential energy. When the electron returns to the ground state, it releases this energy in the form of a photon. The wavelength of the emitted photon is directly related to the energy difference between the excited state and the ground state, as described by the Planck-Einstein relation: $E = hc/\lambda$, where $E$ is the energy of the photon, $h$ is Planck's constant, $c$ is the speed of light, and $\lambda$ is the wavelength of the photon. This relationship between excited states and the properties of the electromagnetic spectrum is crucial for understanding the behavior of atoms and molecules, as well as the applications of spectroscopy.
• Analyze how the concept of excited states can be used to explain the absorption and emission of specific wavelengths of light by atoms and molecules.
  • The discrete nature of excited states in atoms and molecules is the fundamental basis for the absorption and emission of specific wavelengths of light. When an atom or molecule absorbs a photon, the energy of the photon can be used to promote an electron to a higher energy level, creating an excited state. The energy difference between the excited state and the ground state determines the wavelength of the photon that was absorbed. Conversely, when an electron in an excited state returns to the ground state, it releases the stored energy in the form of a photon with a wavelength that is also determined by the energy difference between the two states. This process of absorption and emission of specific wavelengths of light is the foundation for many spectroscopic techniques used to study the structure and properties of atoms and molecules, as well as the behavior of the electromagnetic spectrum.

Related terms

Ground State: The lowest possible energy state of an atom or molecule, where electrons occupy the innermost, most stable energy levels.

Quantum Leap: The discrete, instantaneous transition of an electron from one energy level to another, without passing through intermediate states.

Photon Emission:

The process by which an electron in an excited state releases a photon (light particle) to return to a lower energy level.