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Calculate The Wavelength of Light Emitted N 5 N 3

Reviewed by Calculator Editorial Team

When an electron transitions from a higher energy level to a lower one in a hydrogen atom, it emits light with a specific wavelength. This calculator helps determine the wavelength of light emitted when an electron moves from n=5 to n=3 using the Rydberg formula.

How to calculate the wavelength

The wavelength of emitted light can be calculated using the Rydberg formula, which relates the wavelength to the energy levels of the electron. The formula accounts for the difference in energy between the initial and final states of the electron.

The Rydberg formula

The wavelength (λ) of light emitted when an electron transitions from level n1 to n2 is given by:

1/λ = R(1/n22 - 1/n12)

Where:

  • R is the Rydberg constant (1.0973731 × 107 m-1)
  • n1 is the initial energy level (higher number)
  • n2 is the final energy level (lower number)

For the specific case of n=5 to n=3, we can plug these values into the formula to find the wavelength.

The Rydberg formula

The Rydberg formula is a fundamental equation in atomic physics that describes the wavelengths of light emitted by atoms. It's particularly useful for hydrogen and hydrogen-like atoms where the electron transitions between energy levels.

Key assumptions

The Rydberg formula makes the following assumptions:

  • The atom is in its ground state before emission
  • The electron transitions occur instantaneously
  • Relativistic and quantum electrodynamic effects are negligible
  • The atom is isolated and not affected by external fields

The formula can be rearranged to solve for wavelength:

λ = 1 / [R(1/n22 - 1/n12)]

Worked example

Let's calculate the wavelength for a transition from n=5 to n=3:

  1. Identify the initial and final energy levels: n1 = 5, n2 = 3
  2. Plug the values into the formula:

1/λ = 1.0973731 × 107 (1/32 - 1/52)

1/λ = 1.0973731 × 107 (1/9 - 1/25)

1/λ = 1.0973731 × 107 (0.1111 - 0.04)

1/λ = 1.0973731 × 107 × 0.0711

1/λ ≈ 7.768 × 105 m-1

λ ≈ 1/7.768 × 105 ≈ 1.287 × 10-6 m or 1287 nm

This calculation shows that light with a wavelength of approximately 1287 nanometers is emitted when an electron transitions from n=5 to n=3.

Interpreting the results

The wavelength calculated represents the characteristic light emitted during the electron transition. This wavelength corresponds to a specific color in the electromagnetic spectrum:

  • 1287 nm falls in the infrared region of the spectrum
  • This is not visible to the human eye
  • The energy of the photon can be calculated from the wavelength using Planck's equation: E = hc/λ

Practical applications

The wavelength calculation is important in:

  • Spectroscopy to identify atomic elements
  • Laser technology development
  • Understanding atomic structure and energy levels
  • Designing optical instruments and detectors

Frequently asked questions

What is the Rydberg constant?

The Rydberg constant (R) is a fundamental physical constant that appears in the Rydberg formula. Its value is approximately 1.0973731 × 107 m-1 and represents the reciprocal of the wavelength of light emitted when an electron transitions between the first excited state and the ground state in a hydrogen atom.

Can this formula be used for other atoms besides hydrogen?

Yes, the Rydberg formula can be adapted for hydrogen-like atoms (atoms with a single electron) by adjusting the Rydberg constant. For multi-electron atoms, more complex quantum mechanical methods are required.

What units should be used for the wavelength?

The wavelength is typically expressed in meters, but nanometers (nm) are commonly used for visible and near-visible light wavelengths. The calculator converts the result to nanometers for easier interpretation.

How accurate is this calculation?

The calculation is accurate within the assumptions of the Rydberg formula. For precise measurements, quantum electrodynamic corrections and relativistic effects may need to be considered.