Which of the following electron transitions in the hydrogen atom will result in the absorption of light?

• A. n = 4 to n = 1
• B. n = 2 to n = 4
• C. n = 2 to n = 1
• D. n = 3 to n = 2

Answer: (B)

Verified step by step guidance

1. Understand that absorption of light occurs when an electron moves from a lower energy level to a higher energy level in an atom.
2. Recall that in the hydrogen atom, energy levels are denoted by the principal quantum number \( n \), where \( n = 1 \) is the ground state and higher \( n \) values correspond to excited states.
3. Identify which transitions involve moving from a lower \( n \) to a higher \( n \) (i.e., \( n_{initial} < n_{final} \)) because these require energy absorption.
4. Analyze each given transition: \( n=4 \to n=1 \) is from higher to lower (emission), \( n=2 \to n=4 \) is from lower to higher (absorption), \( n=2 \to n=1 \) is from higher to lower (emission), and \( n=3 \to n=2 \) is from higher to lower (emission).
5. Conclude that only the transition \( n=2 \to n=4 \) involves absorption of light because the electron gains energy moving to a higher energy level.