Frequently Asked Questions
Because a single incorrect term like “always”, “never”, or “only” can make an otherwise correct statement false, testing precision of conceptual understanding.
Check whether the values satisfy allowed limits such as \( n \ge 1 \), \( 0 \le l \le n-1 \), and \( m_l = -l \text{ to } +l \).
In multi-electron atoms, energy depends on both \( n \) and \( l \) due to shielding and penetration effects.
Bohr’s model does not include electron spin or relativistic corrections, so it cannot explain fine structure splitting.
The correct formula is \( 2n^2 \), derived from quantum mechanical considerations.
4s is lower in neutral atoms initially, but after ionization 3d becomes lower in energy.
According to Heisenberg’s uncertainty principle \( \Delta x \Delta p \ge \frac{\hbar}{2} \), exact position and momentum cannot be simultaneously known.
Isotopes differ in mass number, affecting properties like density and rate of diffusion.
Probability density is given by \( \psi^2 \), not \( \psi \) itself.
The energy is negative because it is measured relative to zero at infinite separation.
While degenerate in energy, d-orbitals have different spatial orientations and shapes.
Exceptions occur due to half-filled and fully filled subshell stability (e.g., Be vs B).
Lyman transitions end at \( n=1 \) and lie in the ultraviolet region.
Correct expression is \( \sqrt{l(l+1)}\hbar \), not simply \( n\hbar \).
Only s-orbitals are spherical; p and d orbitals have distinct shapes.