Final answer:
In the molecule SO3, the bonds between sulfur (S) and oxygen (O) are polar covalent due to the difference in electronegativity between the two nonmetal atoms, with no ionic bonds present.
Step-by-step explanation:
The types of bonds present in the molecule SO3 are determined by examining the electronegativities of the atoms involved and the resulting electron distribution. Sulfur (S) and oxygen (O) are both nonmetals and therefore typically form covalent bonds. Since oxygen is more electronegative than sulfur, the shared electrons will be pulled more towards the oxygen atoms, leading to a bond where the electron density is not equally shared. This results in polar covalent bonds. There are no metal atoms in SO3, excluding the possibility of ionic bonds, which generally occur between metals and nonmetals. Consequently, the types of bonds present in SO3 are polar covalent bonds.