Final answer:
The zinc ion in zinc oxide has no valence electrons, as its two valence electrons are lost when it forms a Zn²⁺ ion. Oxygen has six valence electrons. In total, zinc oxide as a compound would involve eight valence electrons in bonding.
Step-by-step explanation:
The number of valence electrons in zinc oxide (ZnO) involves considering the valence electrons of zinc (Zn) and oxygen (O) separately. Zinc, with an electronic configuration of [Ar]4s²3d², loses two electrons to form Zn²⁺, leaving the 3d orbital completely filled with no valence electrons actively participating in the bonding. Oxygen, in group 16, has six valence electrons. When zinc oxide forms, oxygen also participates in the bonding with its six valence electrons.
In a molecule of zinc oxide, each zinc atom donates its two valence electrons and each oxygen atom uses its six valence electrons for bonding. However, the term 'valence electrons' typically refers to the electrons that are used to form bonds in compounds, which in the case of ZnO, would be the two electrons from zinc and six from oxygen. Therefore, in a ZnO molecule, eight valence electrons are involved in bonding.