Is BaSO4 soluble in HNO3?
The correct answer and explanation is:
BaSO4 (barium sulfate) is not soluble in nitric acid (HNO3) under standard conditions.
Explanation:
Barium sulfate is an ionic compound composed of barium ions (Ba²⁺) and sulfate ions (SO₄²⁻), and it is known for its very low solubility in water. This low solubility stems from the strong ionic bonds between Ba²⁺ and SO₄²⁻, which make it difficult for water molecules to break apart the crystal lattice of BaSO4. The solubility product constant (Ksp) of BaSO4 in water is very small, indicating that only a tiny amount of it can dissolve.
When BaSO4 is placed in nitric acid (HNO3), a strong acid, it does not readily dissolve. This is because nitric acid dissociates into H⁺ and NO₃⁻ ions in solution, but neither of these ions can break the strong bond between Ba²⁺ and SO₄²⁻. The acid may help to dissolve other salts or minerals by increasing the availability of H⁺ ions, which can protonate anions like carbonate (CO₃²⁻), for example, but it does not significantly affect the sulfate ions in BaSO4.
However, in the presence of very concentrated nitric acid or under specific conditions, such as extremely high temperatures, BaSO4 might undergo a reaction where the sulfate is converted to a more soluble form, but under typical conditions, it remains insoluble. This is why BaSO4 is considered insoluble in nitric acid in practical settings.
In conclusion, BaSO4 is essentially insoluble in HNO3 at normal conditions, due to the strong ionic bonds in the crystal lattice that are not easily broken by the HNO3 ions.