Question

Identify the net ionic equation from the following pair of reactants. Use the solubility to determine the products when necessary. The reactants will react to form products, though not necessarilyinsoluble products.

Answer 1

We are given these reactants:

H₂SO₄ (aq) + BaCl₂ (aq) ----> ?

BaCl₂ is a soluble salt, so it will dissociate into its ions.

BaCl₂ (aq) ---> Ba²⁺ (aq) + 2 Cl⁻ (aq)

Something similar happens with H₂SO₄, since it is a strong acid it will dissociate into its ions.

H₂SO₄ (aq) ---> 2 H⁺ (aq) + SO₄²⁻ (aq)

Now we can work on the equations. This is a double replacement equation so the molecular equation will be:

H₂SO₄ (aq) + BaCl₂ (aq) ----> 2 HCl (aq) (aq) + BaSO₄ (s)

BaSO₄ is an insoluble salt of Barium, and HCl is a strong acid.

So if we divide the molecular equation in the ions we get the ionic equation:

H₂SO₄ (aq) + BaCl₂ (aq) ----> 2 HCl (aq) (aq) + BaSO₄ (s)

2 H⁺ (aq) + SO₄²⁻ (aq) + Ba²⁺ (aq) + 2 Cl⁻ (aq) ---> 2 H⁺ (aq) + 2 Cl⁻ (aq) + BaSO₄ (s)

And if we cancel out the ions that we have on both sides we get the net ionic equation.

SO₄²⁻ (aq) + Ba²⁺ (aq) ---> BaSO₄ (s)

Answer: First option: SO₄²⁻ (aq) + Ba²⁺ (aq) ---> BaSO₄ (s)