Answer:
80g
Explanation:
2H2 + O2 —> 2H2O
MM of H2O = (2x1) + 16 = 2 + 16 = 18g/mol
Mass conc. of H2O from the balanced equation = 2 x 18 = 36g
MM of O2 = 16 x 2 = 32g/mol
From the equation,
32g of O2 reacted to produce 36g of H2O.
Therefore Xg of O2 will react to produce 90g of H2O i.e
Xg of O2 = (32x90)/36 = 80g