Which of the following is true about the absorption and emission of energy by an atom?a)At low temperatures, the lines in the absorption spectrum of an atom coincide with the lines in its emission spectrum that represent transitions to the ground slateb)An atom can emit photons of only certain specific energies.c)An atom can emit photons of any energy.d)An atom can only absorb photons that have certain specific energies.Correct answer is option 'A,B,D'. Can you explain this answer?

Question

Answer

E = hv = E_f – E_in

The frequency can only corresponds to the difference in two energy states.
The correct answers are: An atom can only absorb photons that have certain specific energies., An atom can emit photons of only certain specific energies., At low temperatures, the lines in the absorption spectrum of an atom coincide with the lines in its emission spectrum that represent transitions to the ground slate

Answer

Absorption Spectra: An absorption spectrum can be defined as a spectrum obtained by transmitting electromagnetic radiation through a substance.

Emission Spectra: Emission spectrum can be defined as a spectrum of the electromagnetic radiation emitted by a substance

Answer

Introduction:
The absorption and emission of energy by an atom play a crucial role in understanding the behavior of atoms and the interactions between light and matter. This process can be explained using the concept of energy levels and transitions within an atom.

Absorption Spectrum:
- At low temperatures, when an atom is in its ground state, it can absorb photons of specific energies.
- The absorption spectrum of an atom consists of a series of dark lines or bands at specific energies.
- These dark lines or bands represent the energy differences between different energy levels within the atom.
- When a photon of the corresponding energy is incident on the atom, it can be absorbed, causing an electron to be excited to a higher energy level.

Emission Spectrum:
- When an atom is excited to a higher energy level, it can emit photons as it returns to a lower energy level.
- The emission spectrum of an atom consists of a series of bright lines or bands at specific energies.
- These bright lines or bands represent the energy differences between the excited state and the ground state of the atom.
- Each line corresponds to a specific transition between energy levels.

Relationship between Absorption and Emission Spectra:
- At low temperatures, the lines in the absorption spectrum of an atom coincide with the lines in its emission spectrum that represent transitions to the ground state.
- This is because when an atom absorbs a photon and gets excited to a higher energy level, it eventually returns to the ground state by emitting a photon of the same energy.
- Therefore, the absorption and emission spectra of an atom will have common lines or bands, representing the same energy transitions.

Specific Energies of Emitted Photons:
- An atom can emit photons of only certain specific energies.
- This is due to the quantized nature of energy levels within an atom.
- Each energy level corresponds to a specific energy, and when an electron transitions between these levels, it emits or absorbs a photon with an energy equal to the energy difference between the levels.
- The emitted photon's energy is determined by the energy levels involved in the transition and is independent of the incident photon's energy.

Specific Energies of Absorbed Photons:
- Similar to emitted photons, an atom can only absorb photons that have certain specific energies.
- The absorbed photon's energy must match the energy difference between the energy levels involved in the transition.
- If the incident photon's energy does not match any of the possible energy differences within the atom, it will not be absorbed.

Conclusion:
In summary, the absorption and emission of energy by an atom are governed by the specific energy differences between its energy levels. At low temperatures, the absorption and emission spectra coincide, representing transitions to the ground state. An atom can emit and absorb photons of only certain specific energies, determined by the energy differences between the atom's energy levels.

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