Question

rust contains iron(III) oxide .how many moles of iron (III) ions are present in 4.0 g of rust?

Answer 1

27175, Chemistry, Other | Completed

rust contains iron(III) oxide .how many moles of iron (III) ions are present in 4.0 g of rust?

Solution:

Firstly, we determine the molar mass of iron(III) oxide:

$$\mathrm{M(Fe_2O_3)} = 56.2 + 16.3 = 160\ \mathrm{g/mol}$$

Then, we calculate the amount of moles of iron(III) oxide, which it's included in 4.0 g of rust:

$$\mathrm{n(Fe_2O_3)} = \frac{\mathrm{m(Fe_2O_3)}}{\mathrm{M(Fe_2O_3)}} = \frac{4.0}{160} = 0.025\ \mathrm{mole}$$

One mole of Fe₂O₃ includes two moles of iron(III), so 0.025 moles of Fe₂O₃ include 0.025 · 2 = 0.05 moles.

Answer:

The amount of Fe₂O₃ is 0.05 moles.