To calculate the formal charge on the oxygen atom in the sulfate ion SO4 2- , we will use the formula:Formal charge = Valence electrons of the atom - Non-bonding electrons - 1/2 Bonding electrons In the sulfate ion, there are four oxygen atoms bonded to a central sulfur atom. Each oxygen atom forms a double bond with the sulfur atom. The Lewis structure of the sulfate ion can be represented as:O=S=O|| ||O=S=ONow, let's calculate the formal charge on one of the oxygen atoms:1. Valence electrons of oxygen: Oxygen belongs to Group 16 or Group 6A in the periodic table, so it has 6 valence electrons.2. Non-bonding electrons: In the sulfate ion, each oxygen atom has 4 non-bonding electrons 2 lone pairs .3. Bonding electrons: Each oxygen atom forms a double bond with the sulfur atom, which means there are 4 bonding electrons 2 per bond .Now, we can plug these values into the formula:Formal charge = 6 - 4 - 1/2 4 Formal charge = 6 - 4 - 2Formal charge = 0The formal charge on each oxygen atom in the sulfate ion SO4 2- is 0.