1. Determine the number of electrons in each atom:
* Sulfur (S): Sulfur has 16 electrons (its atomic number is 16).
* Oxygen (O): Oxygen has 8 electrons (its atomic number is 8).
2. Calculate the total number of electrons in the neutral molecule (SO₄):
* Sulfur: 16 electrons
* Oxygen (4 atoms): 8 electrons/atom * 4 atoms = 32 electrons
* Total: 16 + 32 = 48 electrons
3. Account for the negative charge:
* The sulfate ion has a 2- charge (SO₄²⁻). This means it has gained two extra electrons.
4. Final calculation:
* 48 electrons (neutral molecule) + 2 electrons (charge) = 50 electrons
Therefore, there are 50 electrons in a sulfate ion (SO₄²⁻).
