Question

4Fe + 3O2 → 2Fe2O3
Iron combines with oxygen to form rust. Given the chemical reaction, how many grams of 4Fe + 3O2 would produce 10 g of rust?
A) 7 g
B) 10 g
C) 30 g
D) 70 g

Answer 1

n(2Fe2O3)=10g/319.374amu=0.03mol

n(4Fe+3O2)=0.03 mol

m(4Fe+2O2)=Mn=319.374×0.03=9.58=10

Answer 2

Answer:

b) 10 g

Explanation:

Hi, the answer in simply: during a chemical reaction (that doesn't involve nuclear processes) the total mass involved is constant.

The total mass of the reactants equals the total mass of the products, althought the number of molecules may vary.