Answer:
The mass of iron needed to react with the oxygen is 70 g.
Explanation:
The balanced chemical reaction between iron and oxygen is given as;
4Fe + 3O₂ ----------> 2Fe₂O₃
Molecular mass of 3O₂: 3(16 x 2) = 96 g
Molecular mass of 4Fe: 4(56) = 224 g
96 g of O₂ ---requires--------> 224 g of Fe
30 g of O₂ -------requires--------->? Fe
= (30 x 224) / 96
= 70 g
Therefore, the mass of iron needed to react with the oxygen is 70 g.
