Question

which is the electron configuration for beryllium? 1s²2s¹ 1s²2s² 1s²2s²2p¹ 1s²2s²2p²

Explanation:

Step1: Determine the atomic number of beryllium

Beryllium has an atomic number of \(4\). This means it has \(4\) electrons.

Step2: Fill the electron orbitals

• The \(1s\) orbital can hold a maximum of \(2\) electrons. So, we first fill \(1s\) with \(2\) electrons: \(1s^{2}\).
• After filling \(1s\), we have \(4 - 2= 2\) electrons left.
• The \(2s\) orbital can also hold a maximum of \(2\) electrons. So, we fill \(2s\) with the remaining \(2\) electrons: \(2s^{2}\).

Answer:

\(1s^{2}2s^{2}\)