Question

The non-metallic element present in the third period other than Sulphur and Oxygen.

Answer 1

1. Third Period Elements: The third period of the periodic table has eight elements: Sodium (Na), Magnesium (Mg), Aluminum (Al), Silicon (Si), Phosphorus (P), Sulphur (S), Chlorine (Cl), and Argon (Ar).
2. Non-metallic character across a period: As we move across a period, the non-metallic character increases. Thus, in the third period, Sodium, Magnesium, and Aluminum are metals, Silicon is a metalloid, and Phosphorus, Sulphur, and Chlorine are non-metals.
3. Hence, the non-metallic element present in the third period other than Sulphur is Phosphorus (P) or Chlorine (Cl).