Respuesta :

Mole Road Map:
                       ÷             ×
Mass (grams) ⇄ Moles ⇄ Particles (atoms, molecules, etc.)
                       ×             ÷
                        ↓             ↓
             Molar Mass     6.02 × 10^23 (Avogadro's number)

(1.2 × 10^24 atoms of Magnesium) ÷ (6.02 × 10^23) ≈ 2.0 mol Magnesium (according to significant figures)