Here's how you can write the chemical equation for the reaction of aqueous barium chloride (BaCl₂) and sodium fluoride (NaF) to form a precipitate of barium fluoride (BaF₂) and aqueous sodium chloride (NaCl):

1. Balanced Chemical Equation:

BaCl₂(aq) + 2NaF(aq) → BaF₂(s) + 2NaCl(aq)

Explanation:

* (aq) indicates that the substance is dissolved in water (aqueous solution).

* (s) indicates that the substance is a solid (precipitate).

* Coefficients: The numbers in front of each compound (1, 2, 1, 2) balance the equation, ensuring the same number of atoms of each element on both sides of the reaction.

2. Ionic Equation:

Ba²⁺(aq) + 2Cl⁻(aq) + 2Na⁺(aq) + 2F⁻(aq) → BaF₂(s) + 2Na⁺(aq) + 2Cl⁻(aq)

* In the ionic equation, we separate the soluble ionic compounds into their individual ions.

3. Net Ionic Equation:

Ba²⁺(aq) + 2F⁻(aq) → BaF₂(s)

* The net ionic equation only shows the ions that directly participate in the formation of the precipitate. The spectator ions (Na⁺ and Cl⁻) that are present on both sides of the reaction are removed.

Key Point: The formation of barium fluoride (BaF₂), an insoluble solid, is the driving force behind this reaction. This is why the reaction proceeds and a precipitate is formed.