Here's how to write the molecular equation for the reaction between iron(III) nitrate and ammonium carbonate:

1. Identify the reactants and products:

* Reactants:

* Iron(III) nitrate: Fe(NO₃)₃ (aq)

* Ammonium carbonate: (NH₄)₂CO₃ (aq)

* Products:

* Iron(III) carbonate: Fe₂(CO₃)₃ (s) (insoluble in water)

* Ammonium nitrate: NH₄NO₃ (aq)

2. Write the unbalanced equation:

Fe(NO₃)₃ (aq) + (NH₄)₂CO₃ (aq) → Fe₂(CO₃)₃ (s) + NH₄NO₃ (aq)

3. Balance the equation:

2 Fe(NO₃)₃ (aq) + 3 (NH₄)₂CO₃ (aq) → Fe₂(CO₃)₃ (s) + 6 NH₄NO₃ (aq)

Therefore, the balanced molecular equation is:

2 Fe(NO₃)₃ (aq) + 3 (NH₄)₂CO₃ (aq) → Fe₂(CO₃)₃ (s) + 6 NH₄NO₃ (aq)