Question

Write the electron configuration and determine the valency of the beryllium -atomic number 4 and oxygen - atomic number 8.

Answer 1

Beryllium (Atomic No. 4)

• Electron Configuration: 2, 2
• Valency: 2 (It loses 2 electrons to become stable).

Oxygen (Atomic No. 8)

• Electron Configuration: 2, 6
• Valency: 2 (It needs to gain 2 electrons to complete its octet).