Question

(a) 1s and 2s orbitals are similar in the following ways:

symmetry around the nucleus
distance of electrons from the nucleus
holds a maximum of 2 electrons
size of the orbital
orbital shape

Explanation:

• Symmetry around the nucleus: Both \(1s\) and \(2s\) orbitals are spherically symmetric around the nucleus.
• Holds a maximum of 2 electrons: According to the Pauli exclusion principle, each orbital (whether \(1s\) or \(2s\)) can hold a maximum of 2 electrons with opposite spins.
• Orbital shape: Both \(1s\) and \(2s\) orbitals have a spherical shape. The \(2s\) orbital has a radial node (a region where the probability of finding an electron is zero), but the basic shape (spherical) is the same as that of the \(1s\) orbital.
• Distance of electrons from the nucleus: The \(2s\) orbital is on average farther from the nucleus than the \(1s\) orbital. As the principal quantum number \(n\) ( \(n = 1\) for \(1s\), \(n=2\) for \(2s\)) increases, the electron - nucleus distance (on average) increases.
• Size of the orbital: The \(2s\) orbital is larger in size than the \(1s\) orbital. As \(n\) increases, the spatial extent of the orbital (related to the electron's probability distribution) increases.

Answer:

symmetry around the nucleus, holds a maximum of 2 electrons, orbital shape.