The Chemical Reaction

Carbonates (CO₃²⁻) react with acids (H⁺) in a double displacement reaction. This means that the positive and negative ions switch partners.

1. The Acid Provides Hydrogen Ions (H⁺): Acids release hydrogen ions (H⁺) in solution.

2. The Carbonate Provides Carbonate Ions (CO₃²⁻): Carbonates contain the carbonate ion (CO₃²⁻).

3. Formation of Water and Carbon Dioxide: The hydrogen ions from the acid react with the carbonate ions to form carbonic acid (H₂CO₃). Carbonic acid is unstable and quickly decomposes into water (H₂O) and carbon dioxide (CO₂).

The Equation:

The general equation for this reaction is:

```

2H⁺ (aq) + CO₃²⁻ (aq) → H₂O (l) + CO₂ (g)

```

Explanation:

* (aq) denotes species dissolved in water (aqueous solution)

* (l) denotes a liquid (water)

* (g) denotes a gas (carbon dioxide)

Example:

Consider the reaction of hydrochloric acid (HCl) with calcium carbonate (CaCO₃):

```

2HCl (aq) + CaCO₃ (s) → CaCl₂ (aq) + H₂O (l) + CO₂ (g)

```

Key Points:

* The reaction is exothermic, meaning it releases heat.

* The production of carbon dioxide gas is often observed as fizzing or bubbling.

* This reaction is used in many applications, including the production of baking soda (sodium bicarbonate, NaHCO₃).

Let me know if you have any other questions!