Question

What is the net ionic equation of the reaction of FeCl2 with NaOH? Express you answer as a chemical equation including phases.

Answer 1

Fe²⁺(aq) + 2OH⁻(aq) → Fe(OH)₂(s)

Step-by-step explanation:

To determine the reaction, we define the reactants:

FeCl₂, NaOH

We dissociate them:

FeCl₂(aq) → Fe²⁺(aq) + 2Cl⁻ (aq)

NaOH (aq) → Na⁺ (aq) + OH⁻(aq)

Salts from chloride are soluble, except for Ag⁺, Pb²⁺, Hg₂²⁺, Cu⁺

The OH⁻ and the Fe²⁺ bonds to make a precipitate.

So, the molecular complete equation is:

FeCl₂(aq) + 2NaOH(aq) → Fe(OH)₂(s) ↓ + 2NaCl(aq)

When we dissociate the elements, we get the net ionic equation but as we produced an state's change, the compound stays the same.

We cancel the spectators ions (the ones, that are repeated)

Fe²⁺(aq) + 2Cl⁻ (aq) + 2Na⁺ (aq) + 2OH⁻(aq) → Fe(OH)₂(s) + 2Na⁺(aq) + 2Cl⁻(aq)

Fe²⁺(aq) + 2OH⁻(aq) → Fe(OH)₂(s)