Which of the following contains the maximum number of atoms?

Number of atoms($N$) = Number of moles($n$) $\times {N_2\times }^{ }$ atomicity
Where, $N_2$ = Avogadro's number = $6.023\times 10^{23}$
 

• 2.0 mol S₈ = 2.0 mol x 6.02x10²³ molecules/mol x 8 atoms/molecule = 9.6x10²⁴ atoms
• 6 mol S = 6 moles x 6.02x10²³ atoms/mol = 3.6x10²⁴ atoms
• 2.0 mol SO₂ = 2.0 mol x 6.02x10²³ molecules/mol x 3 atoms/molecule =3.6 x10²⁴ atoms
•  44.8 L CO₂ @ STP = $\frac{44.8 L \times 1 L/dm3 \times 1 mol}{22.4 L}$ 6.02x10²³ molecules/mol x 3 atoms/molecule = 3.6x10²⁴ atoms

$S_8$ contains  9.6x10²⁴ atoms, the most atoms, at $2$ moles.

Therefore, 2.0 moles of $S_8$ contains the maximum number of atoms.