Question

A metal x with relative atomic mass 56 forms an oxide with formula x=O3. How many grams of the metal will combine with 10 grams of oxygen?o=16

Answer 1

2M + 3O2 ==> 2MO3

mols O2 = g/molar mass = 10/32 = 0.312. Convert to mols M needed.
mols M = 0.312 mols O2 x (2 mols M/3 mols O2) = 0.312 x 2/3 = 0.208
grams M = mols M x atomic mass M = ?