Here's why:

* Atomic Size Trends: Atomic size generally increases as you move down a group (column) on the periodic table. This is because you add an extra electron shell with each period.

* Location: Silicon (Si) is in Group 14, while sulfur (S) is in Group 16. Both are in the third period.

* Electronegativity: Sulfur is more electronegative than silicon, meaning it has a stronger pull on its electrons. This also contributes to its larger atomic size.

Therefore, sulfur is located further down the periodic table and has a larger atomic size than silicon.