Question

What element has the following electron configuration? 1s² 2s² 2p⁶ 3s¹

a) Magnesium
b) Sodium
c) Beryllium
d) Potassium

Answer 1

The element with the electron configuration 1s² 2s² 2p 3s¹ is sodium.

Step-by-step explanation:

The element with the electron configuration 1s² 2s² 2p⁶3s¹ is sodium (Na). To identify the element, we need to count the total number of electrons described by the electron configuration, which gives us 11 electrons. This corresponds to sodium, which is the element with the atomic number 11 on the periodic table. Sodium's complete electron configuration is exactly 1s² 2s² 2p⁶ 3s¹.

• 1s²: This represents the filling of the 1s sublevel with two electrons.
• 2s²: This represents the filling of the 2s sublevel with two electrons.
• 2p⁶: This represents the filling of the 2p sublevel with six electrons.
• 3s¹: This represents the filling of the 3s sublevel with one electron.