**Answer:**

The empirical formula is: Fe(CO)₅

**Explanation:**

According the global reaction:

Feₓ(CO)y + O₂ → Fe₂O₃ + CO₂

You should calculate Fe₂O₃ and CO₂ moles, thus:

0,799 Fe₂O₃ grams × =** 5,00×10⁻³ Fe₂O₃ moles**

2,200 CO₂ grams × =** 5,00×10⁻²CO₂ moles**

The ratio between Fe₂O₃ moles and CO₂ moles is 1:10. Thus ratio between x and y must be 1:5 because Fe₂O₃ has 2 irons but CO₂ has just one carbon.

Assuming the formula is Fe₁(CO)₅ the molecular weight is 195,9 g/mol. Thus:

1,959 Fe(CO)₅ grams × =** 1,00×10⁻² Fe(CO)₅ moles**

Thus, assuming 1,00×10⁻² moles as basis for calculation, the global reaction is:

**1 **Fe(CO)₅ + **¹³/₂**O₂ → **¹/₂ **Fe₂O₃ + **5 **CO₂

With this balanced equation the moles produced have sense, thus, the empirical formula is: **Fe(CO)₅**

I hope it helps!