Bonjour...
1) M(N₂O) = 2xM(N) + M(O) = 2x14,0 + 16,0 = 44,0 g.mol⁻¹
2) V = 50,0 mL = 50,0.10⁻³ L
n(N₂O) = V/Vm avec Vm, volume molaire = 25,0 L.mol⁻¹
Soit : n(N₂O) = 50,0.10⁻³/25,0 = 2,00.10⁻³ mol
3) m(N₂O) = n(N₂O) x M(N₂O)
Soit : m(N₂O) = 2,00.10⁻³ x 44,0 = 8,80.10⁻² g (ou 88,0 mg)
