Chemistry Regents Practice Test 2025 – The All-in-One Guide to Exam Success!

The electron configuration of an atom provides detailed information about the arrangement of electrons in the atomic orbitals. It indicates how electrons are distributed among the different energy levels and subshells. This arrangement is crucial because it determines many of the chemical properties of the atom, including how it interacts with other atoms and what kind of bonds it can form.

The electron configuration follows a specific set of rules, such as the Aufbau principle, Pauli exclusion principle, and Hund's rule, which dictate that electrons fill the lowest energy orbitals first, that each orbital can hold a maximum of two electrons with opposite spins, and that electrons will occupy degenerate orbitals singly before pairing up, respectively.

Taking into account the other options: the number of protons in the nucleus pertains to the atomic number, the number of isotopes relates to variations of the same element with different neutron counts, and the bonds formed with neighboring atoms are influenced by the electron configuration but are not directly described by it. Hence, the essence of what the electron configuration conveys is the arrangement of electrons, making that choice the correct response.