Electron Distribution in Carbon and Sodium Atoms

Before writing electron distributions, understand the key rules:

1. The maximum number of electrons in any shell = 2n² (where n = shell number)
   • Shell 1 (K): max 2 electrons
   • Shell 2 (L): max 8 electrons
   • Shell 3 (M): max 18 electrons
2. The outermost shell cannot have more than 8 electrons
3. Electrons fill the innermost shell first before moving to the next

Atomic Number of Carbon = 6 This means carbon has 6 protons and 6 electrons (in a neutral atom).

Distribution:

• Shell 1 (K): 2 electrons (shell filled to maximum)
• Shell 2 (L): 4 electrons (remaining 6−2 = 4)

Carbon electron distribution: 2, 4

Since carbon has 4 electrons in its outermost shell (valence electrons = 4), it can form 4 covalent bonds. This is why carbon forms such an enormous variety of compounds (organic chemistry).

Atomic Number of Sodium = 11 Sodium has 11 protons and 11 electrons.

Distribution:

• Shell 1 (K): 2 electrons (maximum for this shell)
• Shell 2 (L): 8 electrons (maximum for this shell)
• Shell 3 (M): 1 electron (remaining 11−2−8 = 1)

Sodium electron distribution: 2, 8, 1

Since sodium has only 1 electron in its outermost shell, it readily loses this electron to achieve a stable octet — forming the Na⁺ ion. This makes sodium a highly reactive metal.

• Carbon's valency = 4 (needs 4 more electrons to complete octet)
• Sodium's valency = 1 (loses 1 electron easily)