Which statement correctly maps orbital letters to angular momentum numbers?

• A. s has L = 2; p has L = 3; d has L = 1; f has L = 0.
• B. s has L = 0; p has L = 1; d has L = 2; f has L = 3.
• C. s has L = 3; p has L = 2; d has L = 1; f has L = 0.
• D. s has L = 0; p has L = 2; d has L = 1; f has L = 3.

Answer: (B)

Mapping orbital letters to angular momentum numbers follows a simple, standard sequence: s corresponds to L = 0, p to L = 1, d to L = 2, and f to L = 3. This angular momentum quantum number (often denoted l) comes from solving the angular part of the electron’s wavefunction and determines the orbital’s shape and nodal structure. S orbitals are spherical (l = 0), p orbitals have a dumbbell shape with a nodal plane (l = 1), d orbitals are more complex with four lobes (l = 2), and f orbitals are even more intricate (l = 3). Therefore, the mapping s → 0, p → 1, d → 2, f → 3 is the correct one. The other proposed mappings conflict with the established sequence and the observed orbital shapes.