You're asking about the wavelength of light emitted when an electron transitions from the n=5 to n=3 energy level in an atom. To solve this, we'll need to use the Rydberg formula:

1/λ = R (1/n₁² - 1/n₂²)

where:

* λ is the wavelength of the emitted light

* R is the Rydberg constant (approximately 1.097 x 10⁷ m⁻¹)

* n₁ is the lower energy level (n=3 in this case)

* n₂ is the higher energy level (n=5 in this case)

Let's plug in the values:

1/λ = (1.097 x 10⁷ m⁻¹) (1/3² - 1/5²)

1/λ = (1.097 x 10⁷ m⁻¹) (1/9 - 1/25)

1/λ = (1.097 x 10⁷ m⁻¹) (16/225)

1/λ ≈ 7.82 x 10⁵ m⁻¹

Now, solve for λ:

λ ≈ 1.28 x 10⁻⁶ m

Therefore, the wavelength of light emitted during this transition is approximately 1.28 x 10⁻⁶ meters, or 1280 nanometers. This falls within the infrared region of the electromagnetic spectrum.