Balanced chemical reaction of BaCl2 + H2SO4 –> BaSO4 + 2HCl
The correct answer and explanation is:
The balanced chemical reaction between barium chloride (BaCl₂) and sulfuric acid (H₂SO₄) is:
BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl
Explanation:
In this reaction, barium chloride reacts with sulfuric acid to form barium sulfate and hydrochloric acid. Barium chloride is an ionic compound consisting of Ba²⁺ and Cl⁻ ions, while sulfuric acid is a strong acid that dissociates into H⁺ and SO₄²⁻ ions in aqueous solution.
When these two compounds mix, the barium ions (Ba²⁺) from BaCl₂ combine with the sulfate ions (SO₄²⁻) from H₂SO₄ to form barium sulfate (BaSO₄), which is an insoluble solid and precipitates out of the solution. This precipitation reaction is a classic example of a double displacement (or metathesis) reaction.
The chloride ions (Cl⁻) from BaCl₂ pair with the hydrogen ions (H⁺) from sulfuric acid to produce hydrochloric acid (HCl), which remains dissolved in the solution.
Balancing the equation requires ensuring the number of atoms of each element is the same on both sides. The reactants have:
- 1 Ba atom in BaCl₂
- 2 Cl atoms in BaCl₂
- 2 H atoms in H₂SO₄
- 1 S atom in H₂SO₄
- 4 O atoms in H₂SO₄
On the products side:
- 1 Ba atom in BaSO₄
- 1 S atom in BaSO₄
- 4 O atoms in BaSO₄
- 2 H atoms in 2HCl
- 2 Cl atoms in 2HCl
All elements are balanced, so the chemical equation is correct.
This reaction is important in qualitative analysis and industrial processes, especially because BaSO₄ is highly insoluble and can be used to test for sulfate ions. The formation of a precipitate indicates the presence of sulfate in a sample. Additionally, barium sulfate has practical applications such as in medical imaging (barium meals) because it is opaque to X-rays and non-toxic when ingested in proper forms.