Quantum Mechanical Model of Atom — Prelims Questions

Which of the following statements is INCORRECT regarding the Quantum Mechanical Model of the Atom?

An electron has a de Broglie wavelength of $1.0 \times 10^{-10}$ m. Calculate its velocity. (Given: Planck's constant $h = 6.626 \times 10^{-34}$ J·s, mass of electron $m_e = 9.109 \times 10^{-31}$ kg)

Which of the following sets of quantum numbers ($n, l, m_l, m_s$) is NOT allowed for an electron in an atom?

How many radial nodes are present in a 4p orbital?

What is the maximum number of electrons that can be accommodated in a subshell with $l=3$?

Which of the following statements best describes the significance of $\Psi^2$ (psi-squared) in the Quantum Mechanical Model?

Which of the following phenomena CANNOT be explained by Bohr's model but IS explained by the Quantum Mechanical Model?