Which of the following electronic transitions in the oxygen atom will result in light emission?

• A. From n = 2 to n = 1
• B. From n = 1 to n = 2
• C. From n = 2 to n = 3
• D. From n = 3 to n = 2

Answer: (D)

Verified step by step guidance

1. Understand that light emission occurs when an electron transitions from a higher energy level to a lower energy level, releasing energy in the form of a photon.
2. Identify the direction of each transition: from n = 2 to n = 1 is a drop to a lower energy level, from n = 1 to n = 2 is a jump to a higher energy level, from n = 2 to n = 3 is a jump to a higher energy level, and from n = 3 to n = 2 is a drop to a lower energy level.
3. Recall that transitions from lower to higher energy levels (excitation) require energy absorption and do not emit light, while transitions from higher to lower energy levels (relaxation) result in light emission.
4. Conclude that only transitions from n = 2 to n = 1 and from n = 3 to n = 2 will result in light emission because they involve electrons moving to lower energy levels.
5. Summarize that the key concept is that emission of light corresponds to electrons falling to lower energy states, releasing energy as photons.