## Chemistry: The Molecular Science (5th Edition)

$4.1\ g$ $He$ has the greater mass.
- $6.022 \times 10^{23}$ $He$ atoms: $6.022 \times 10^{23}$ atoms = 1 mol Molar mass $(He)$ = 4.0g/mol Therefore, 1 mol $He$ = 4.0 g $4.1g > 4.0g$ In mass: 4.1 g $He$ > $6.022 \times 10^{23}$ $He$ atoms.