Chemistry: The Molecular Science (5th Edition)

1 mol $I_2$ has the greater mass.
- 1 mol $I_2$: 1 mol = $6.022 \times 10^{23} molecules$ - Since we are comparing quantities of the same compound $(I_2)$, the one with the higher number of molecules has the greater mass. Therefore: In mass: 1 mol $I_2$ > 1 molecule $I_2$