Question

Approximately 1 mL of two clear, colorless solutions, 0.1 M Ba(NO3)2 and 0.1 M Na2SO4, were combined. Upon mixing, a thick milky white precipitate formed. After centrifugation, the solution above the precipitate was found to be clear and colorless. Based on the these observations, determine if a reaction occurred. If so, what is the net ionic equation for the reaction.

Answer 1

Ba²⁺(aq) + SO₄²⁻(aq) ⇒ BaSO₄(s)

Step-by-step explanation:

Let's consider the molecular equation for the reaction between Ba(NO₃)₂ and Na₂SO₄. This is a double displacement reaction in which BaSO₄ forms a white precipitate.

Ba(NO₃)₂(aq) + Na₂SO₄(aq) ⇒ BaSO₄(s) + 2 NaNO₃(aq)

The complete ionic equation includes all the ions and insoluble species.

Ba²⁺(aq) + 2 NO₃⁻(aq) + 2 Na⁺(aq) + SO₄²⁻(aq) ⇒ BaSO₄(s) + 2 Na⁺(aq) + 2 NO₃⁻(aq)

The net ionic equation includes only the ions that participate in the reaction and insoluble species.

Ba²⁺(aq) + SO₄²⁻(aq) ⇒ BaSO₄(s)