Orbitals — Shapes of s, p, d orbitals
Atomic Structure
9
JEE Qs
8%
Hard
50
min
Visually memorize the shapes and spatial orientations of s, p, and d orbitals, and consistently practice calculating and identifying radial and angular nodes based on quantum numbers.
🧮 Key Formulas
✅ Key Points for JEE
- 1s-orbitals are spherical (non-directional) with (n-1) spherical nodes, representing regions of zero electron probability.
- 2p-orbitals are dumbbell-shaped (directional) with one angular node (a nodal plane) and are oriented along the x, y, or z axes (p_x, p_y, p_z).
- 3d-orbitals are mostly cloverleaf-shaped (directional), except for d_z^2, with two angular nodes and five distinct spatial orientations (d_xy, d_yz, d_zx, d_x^2-y^2, d_z^2).
- 4The shape and orientation of an orbital are primarily determined by the azimuthal (l) and magnetic (m_l) quantum numbers, while size is determined by the principal (n) quantum number.
- 5Nodes (radial and angular) are surfaces or planes where the probability of finding an electron is zero; understanding their number and type for different orbitals is crucial.
⚠️ Common Mistakes
- ✕Confusing 'orbit' (Bohr's concept of fixed path) with 'orbital' (3D probabilistic region around the nucleus).
- ✕Incorrectly identifying the number of radial, angular, or total nodes for a given orbital (e.g., 3p, 4s, 3d).
- ✕Misremembering the specific spatial orientations of the five d-orbitals, especially the unique shape of d_z^2.
- ✕Assuming all d-orbitals are identical in shape or orientation, overlooking the distinct d_z^2 shape and its orientation.
📝 Practice Questions
See allQ57.Given below are two statements : Statement (I) : For a given shell, the total number of allowed orbitals is given by n2 . Statement (II) : For any subshell, the spatial orientation of the orbitals is given by −l to +l values including zero. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are false (2) Statement I is true but Statement II is false (3) Both Statement I and Statement II are true (4) Statement I is false but Statement II is true
Q57.In a multielectron atom, which of the following orbitals described by three quantum numbers will have same energy in absence of electric and magnetic fields? A. n = 1, l = 0, m1 = 0 B. n = 2, l = 0, m1 = 0 C. n = 2, l = 1, m1 = 1 D. n = 3, l = 2, m1 = 1 E. n = 3, l = 2, m1 = 0 Choose the correct answer from the options given below: (1) B and C Only (2) A and B Only (3) C and D Only (4) D and E Only
Q51.Radius of the first excited state of Helium ion is given as : a0 → radius of first stationary state of hydrogen atom. (1) r = 4a0 (2) r = 2a0 (3) r = a02 (4) r = a04
Q62.Given below are two statements : Statement (I) : A spectral line will be observed for a 2px →2py transition. Statement (II) : 2Px and 2py are degenerate orbitals. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are true (2) Statement I is false but Statement II is true (3) Both Statement I and Statement II are false (4) Statement I is true but Statement II is false
Q51.For hydrogen atom, the orbital/s with lowest energy is/are : (A) 4 s (B) 3px (C) 3 dx2−y2 (D) 3 dz2 (E) 4pz Choose the correct answer from the options given below : (1) (B), (C) and (D) only (2) (A) and (E) only (3) (A) only (4) (B) only
Q44.The frequency of revolution of the electron in Bohr's orbit varies with n, the principal quantum number as (1) 1 (2) 1 n4 n2 (3) 1 (4) 1 n n3
NCERT Chapters
- Class 11 Chemistry Ch 2: Structure of Atom