Chemistry - GENERAL CHEMISTRY Question with Solution | TestHub

(A) is correct: Electron probability density approaches zero only at infinity, making a 100% rigid boundary surface impossible to draw.

(B) is correct: An increase in the principal quantum number ($n$) increases both the orbital's distance from the nucleus (size) and its energy.

(C) is incorrect: While all $d$-orbitals in a subshell have the same energy and number of angular nodes (2), $d_{z^2}$ has a unique doughnut-like shape, unlike the clover-leaf shape of the other four.

(D) is correct: The nodal plane of $p_z$ is the $xy$-plane, and the nodal plane of $p_x$ is the $yz$-plane. Only $d_{xy}$ has all its lobes completely within the $xy$-plane without any lobes lying in the $yz$-plane (unlike $p_y$ and $d_{x^2-y^2}$ which have lobes on the y-axis), making the count exactly 1.