Question

match each electron - configuration notation to the neutral element it describes. refer to the periodic table as needed. element: hydrogen (h), sodium (na), oxygen (o), bromine (br). electron configuration notation: 1s^1, ne3s^1, 1s^22s^22p^4, ar4s^23d^104p^5

Explanation:

Step1: Recall electron - configuration rules

Electron configurations are written based on the Aufbau principle, Pauli - exclusion principle, and Hund's rule. We match the given electron configurations to the elements using the atomic number and electron - filling order.

Step2: Match Hydrogen (H)

Hydrogen has an atomic number of 1. Its electron configuration is $1s^1$. So, Hydrogen (H) matches $1s^1$.

Step3: Match Oxygen (O)

Oxygen has an atomic number of 8. The electron - filling order gives its electron configuration as $1s^22s^22p^4$. So, Oxygen (O) matches $1s^22s^22p^4$.

Step4: Match Sodium (Na)

Sodium has an atomic number of 11. Using the noble - gas core notation, with neon (Ne) as the previous noble gas ($Z = 10$), its electron configuration is $[Ne]3s^1$. So, Sodium (Na) matches $[Ne]3s^1$.

Step5: Match Bromine (Br)

Bromine has an atomic number of 35. Using the noble - gas core notation with argon (Ar) as the previous noble gas ($Z = 18$), its electron configuration is $[Ar]4s^23d^{10}4p^5$. So, Bromine (Br) matches $[Ar]4s^23d^{10}4p^5$.

Answer:

Hydrogen (H) - $1s^1$
Oxygen (O) - $1s^22s^22p^4$
Sodium (Na) - $[Ne]3s^1$
Bromine (Br) - $[Ar]4s^23d^{10}4p^5$