Complete and balance the following acid/base reactions. Include solubility state as well. Ba(OH)2(aq) + H3PO4(aq) ? NH3(aq) + H2SO4(aq)
The Correct Answer and Explanation is:
1. Ba(OH)₂(aq) + H₃PO₄(aq) → ?
Step 1: Identify the acid and base
- Ba(OH)₂ is a strong base.
- H₃PO₄ (phosphoric acid) is a weak triprotic acid.
Step 2: Write the products of neutralization
Acid + Base → Salt + Water
Ba(OH)₂ provides 2 OH⁻, and H₃PO₄ provides 3 H⁺, so the reaction ratio is 3 Ba(OH)₂ : 2 H₃PO₄ to form Ba₃(PO₄)₂, a slightly soluble salt, and water.
Balanced Equation:
3Ba(OH)₂(aq) + 2H₃PO₄(aq) → Ba₃(PO₄)₂(s) + 6H₂O(l)
- Ba₃(PO₄)₂ is a precipitate (insoluble in water).
- Water is a liquid formed during neutralization.
2. NH₃(aq) + H₂SO₄(aq) → ?
Step 1: Identify the acid and base
- NH₃ (ammonia) is a weak base.
- H₂SO₄ (sulfuric acid) is a strong diprotic acid.
Step 2: Determine the salt formed
Ammonia reacts with sulfuric acid to form ammonium sulfate, (NH₄)₂SO₄, and no water is directly formed in this neutralization (because ammonia is not hydroxide-based).
Balanced Equation:
2NH₃(aq) + H₂SO₄(aq) → (NH₄)₂SO₄(aq)
- The product, (NH₄)₂SO₄, is soluble in water, hence aqueous.
Final Answers:
1.
3Ba(OH)₂(aq) + 2H₃PO₄(aq) → Ba₃(PO₄)₂(s) + 6H₂O(l)
2.
2NH₃(aq) + H₂SO₄(aq) → (NH₄)₂SO₄(aq)
📘 Explanation (300 words):
Acid-base reactions are fundamental in chemistry and often involve the transfer of hydrogen ions (H⁺) from acids to bases. In a neutralization reaction, an acid reacts with a base to produce a salt and usually water.
In the first reaction, barium hydroxide (Ba(OH)₂), a strong base, reacts with phosphoric acid (H₃PO₄), a weak triprotic acid. Each Ba(OH)₂ unit supplies 2 hydroxide ions (OH⁻), and each H₃PO₄ molecule supplies 3 hydrogen ions (H⁺). To balance the number of H⁺ and OH⁻ ions, we need 3 Ba(OH)₂ molecules and 2 H₃PO₄ molecules. This forms the salt barium phosphate (Ba₃(PO₄)₂) and 6 molecules of water. Barium phosphate is insoluble in water, so it forms a precipitate, indicated as (s).
In the second reaction, ammonia (NH₃), a weak base, reacts with sulfuric acid (H₂SO₄). Ammonia doesn’t contain OH⁻ ions like traditional bases, but it accepts protons (H⁺) to form ammonium ions (NH₄⁺). Each H₂SO₄ molecule provides 2 H⁺ ions, which can protonate 2 NH₃ molecules. The result is the salt ammonium sulfate ((NH₄)₂SO₄), which is soluble in water and remains aqueous.
These reactions demonstrate key principles of acid-base chemistry, solubility rules, and the importance of balancing chemical equations to reflect conservation of mass and charge.
