What is the valency of oxygen?

The valency of oxygen is 2. Valency refers to the ability of an atom to bond with other atoms, which is determined by the number of electrons an atom can gain, lose, or share during a chemical reaction. Oxygen has six electrons in its outer shell and needs to gain two additional electrons to complete its octet and achieve greater stability. This tendency to gain two electrons corresponds to a valency of 2.

In this context, the other options do not accurately reflect the bonding capability of oxygen. A valency of 1 would suggest that oxygen could form one bond, which does not align with its stable configuration. A valency of 4 implies that oxygen could form four bonds, exceeding its electron requirement for stability. A valency of 6 is also incorrect, as it exceeds the number of electrons needed for oxygen to achieve a full valence shell. Therefore, considering its electron structure and bonding needs, a valency of 2 is the accurate assessment for oxygen.