Analysis of the Reaction Between BaCl2 and NaCl in Aqueous Solution

In an aqueous solution, barium chloride (BaCl2) and sodium chloride (NaCl) do not undergo a chemical reaction that produces new products. Instead, they simply coexist as ions in the solution.

Formation of Ions from BaCl2 and NaCl

Both baCl2 and NaCl are water-soluble and dissociate into their respective ions:

For BaCl2:

BaCl2 (aq) → Ba2 (aq) 2 Cl- (aq)

For NaCl:

NaCl (aq) → Na (aq) Cl- (aq)

When these solutions are combined, the resulting solution contains the following ions: Ba2 , Na , Cl- from both BaCl2 and NaCl.

Since all the ions are soluble and no precipitate or gas is formed, the overall result is simply a mixture of these ions in solution.

Another Example: Reaction with Sodium Sulfate

When barium chloride is mixed with sodium sulfate, a white precipitate of barium sulfate (BaSO4) is immediately formed. This reaction results in a change in the ionic composition of the solution due to the exchange of ions. The high insolubility of BaSO4 means it does not go into solution and reacts with the Cl- ions to form a precipitate.

Insolubility of BaSO4 and the Law of Mass Action

BaSO4 is a highly insoluble substance in water, with only 0.002448 g of BaSO4 dissolving in water at 20°C. This means that the concentration of BaSO4 in the solution is limited to a saturation point. According to the law of mass action, the rate of a chemical reaction is directly proportional to the product of the activities or concentrations of the reactants. When the concentration of NaCl is increased, the insoluble white BaSO4 precipitate will increasingly go into solution and eventually disappear.

Factors Affecting Solubility

The solubility of BaSO4 in water can be affected by two main factors:

Increasing the amount of water, which increases the solubility of BaSO4. The effect of sulfate and chloride ions, where sulfate ions increase precipitation, and chloride ions decrease it.

Therefore, by increasing the amount of water or altering the concentrations of the ions involved, the solubility and precipitation of BaSO4 can be controlled.

Conclusion

In conclusion, when barium chloride (BaCl2) and sodium chloride (NaCl) are mixed in an aqueous solution, no chemical reaction produces new products because both salts are soluble and dissociate into ions. However, when these ions react with sodium sulfate, a white precipitate of barium sulfate is formed. The solubility and behavior of these salts are governed by the law of mass action and other physical factors such as the amount of water present in the solution.