AQA GCSE Chemistry Paper 1 Practice Exam 2025 – Complete Study Resource

When metal carbonates react with acids, the products formed are salt, water, and carbon dioxide. This reaction is characterized by an acid-base reaction, where the acid donates protons (H+) and the carbonate ion (CO3^2-) from the metal carbonate reacts with these protons.

The general reaction can be represented as:

\[ \text{Metal Carbonate} + \text{Acid} \rightarrow \text{Salt} + \text{Water} + \text{Carbon Dioxide} \]

For example, if you were to react calcium carbonate (CaCO3) with hydrochloric acid (HCl), you would produce calcium chloride (CaCl2, the salt), water (H2O), and carbon dioxide (CO2), which is released as a gas and can be seen as fizzing or bubbling during the reaction.

This comprehensive outcome of salt, water, and carbon dioxide distinguishes it from other potential reaction product combinations.