The answer is 2.7gm/cm^3 . Density is mass divided by volume .
Answer: when two elements combine, A and B, the ratio of the weight of B combining with A is always a whole number
Explanation:
Balanced equation: 2Fe + 3H2O → Fe2O3 +3H2
Convert g to mols:
285/55.845 = 5.1034 mols
Mole ratio of Iron and Iron (III) Oxide: 2:1
5.1034/2 = 2.5517 mols