Questions: Magnesium (Mg) has atomic number 12. How many electrons does magnesium (Mg) have in its outermost electron shell? (Enter a number such as 1,5,10, etc.)

Magnesium (Mg) has atomic number 12. How many electrons does magnesium (Mg) have in its outermost electron shell? (Enter a number such as 1,5,10, etc.)

Transcript text: Magnesium (Mg) has atomic number 12. How many electrons does magnesium (Mg) have in its outermost electron shell? (Enter a number such as $1,5,10$, etc.)

Solution

Solution Steps

Step 1: Identify the Atomic Number of Magnesium

Magnesium (Mg) has an atomic number of 12. This means it has 12 protons and, in a neutral atom, 12 electrons.

Step 2: Determine the Electron Configuration

The electron configuration of an element describes the distribution of electrons in its atomic orbitals. For magnesium, the electron configuration is: \[ 1s^2 2s^2 2p^6 3s^2 \]

Step 3: Identify the Outermost Electron Shell

The outermost electron shell is the highest energy level that contains electrons. For magnesium, the highest energy level is $ n = 3 $.

Step 4: Count the Electrons in the Outermost Shell

In the electron configuration $ 1s^2 2s^2 2p^6 3s^2 $, the outermost shell (n=3) has 2 electrons in the $ 3s $ orbital.