Answer:
Mg₃N₂ (magnesium nitride)
Explanation:
M(total) = M(mg) + M (n)
M (n) = M(total) - Â M(mg)
    = 0.433g - 0.313g
    = 0.12g
mole (N) = Â 0.12g / 14.0067 g/mol
       = 0.008567
mole Mg = 0.313g / 24.3050 g/mol
       = 0.012878
Mg = 0.012878 / 0.008567
   = 1.5
N = 0.008567 / 0.008567
  = 1
multiply by 2 to get whole numbers
Mg = 1.5 × 2 = 3
N = 1  × 2 = 2
Mg₃N₂ (magnesium nitride)