What is the electron configuration for magnesium (Mg)?The Periodic TableA.3s23p63d4B.1s22s22p63s2C.1s22s22p23s6D.1s22s23s23p6SUBMITarrow_backPREVIOUS

To determine the electron configuration for magnesium (Mg), we first need to know its atomic number, which is 12. This means that a magnesium atom has 12 electrons. The electron configuration represents the distribution of these electrons across the various atomic orbitals.

1. Break Down the Problem

   • Identify the number of electrons in magnesium (12).
   • Distribute these electrons into the appropriate subshells following the Aufbau principle.

2. Relevant Concepts

   • Electrons fill subshells in the order of increasing energy levels: 1s, 2s, 2p, 3s, 3p, and so on.
   • The maximum capacity of each subshell is:
     • 1s can hold 2 electrons,
     • 2s can hold 2 electrons,
     • 2p can hold 6 electrons,
     • 3s can hold 2 electrons.

3. Analysis and Detail

   • Start filling electrons:

     • 1s: 2 electrons → 1s²
     • 2s: 2 electrons → 2s²
     • 2p: 6 electrons → 2p⁶
     • 3s: 2 electrons → 3s²

   • After filling all the subshells, we check the total:

     • 2 (from 1s) + 2 (from 2s) + 6 (from 2p) + 2 (from 3s) = 12 electrons.

4. Verify and Summarize

   • The electron configuration for magnesium is correctly filled based on the principles of electron distribution. There are no electrons left unaccounted for.

Final Answer

The correct electron configuration for magnesium (Mg) is $1s^2 2s^2 2p^6 3s^2$. Therefore, the answer is B. $1s^2 2s^2 2p^6 3s^2$.