The metal is lead, Pb.
One unit of the oxide contains one atom of O (16.00 u).
∴ Mass of oxide = 16.00 u O × (100 u MO/7.17 u O) = 223.15 u MO
Mass of M = mass of MO – mass of O = 223.15 u -16.00 u = 207.2 u
The only element with an atomic mass of 207.2 u is lead (Pb) and the formula of the oxide is PbO.
NH₃:
N = 8*10²²
NA = 6.02*10²³
n = N/NA = 8*10²²/6.02*10²³ ≈ 1.33*10⁻¹=0.133mol
O₂:
N=7*10²²
NA = 6.02*10²³
n = N/NA = 7*10²²/6.02*10²³ = 1.16*10⁻¹=0.116mol
4NH₃ <span>+ 3O</span>₂ ⇒<span> 2N</span>₂<span> + 6H</span>₂<span>O
</span>4mol : 3mol : 2mol
0.133mol : 0.116mol : 0,0665mol
limiting reactant
N₂:
n = 0.0665mol
M = 28g/mol
m = n*M = 0.0665mol*28g/mol = <u>1,862g</u>