Study Notes
Acids can react with alkalis, metal oxides, and carbonates to form different products such as salts, water, and carbon dioxide. Neutralisation involves acids reacting with alkalis to form water and a salt.
- Neutralisation — a reaction where an acid reacts with an alkali to form water and a salt. Example: Hydrochloric acid + sodium hydroxide → sodium chloride + water.
- Acids with Metal Oxides — acids react with metal oxides to form a salt and water. Example: Sulfuric acid + copper oxide → copper sulfate + water.
- Salts — compounds formed when a metal replaces hydrogen in an acid. Example: Hydrochloric acid forms chlorides, sulfuric acid forms sulfates.
- Reactions with Carbonates — acids react with carbonates to produce a salt, carbon dioxide, and water. Example: Hydrochloric acid + copper carbonate → copper chloride + carbon dioxide + water.
- Thermal Decomposition — a reaction where a single compound breaks down into two or more products when heated. Example: Copper carbonate → copper oxide + carbon dioxide.
Exam Tips
Key Definitions to Remember
- Neutralisation: A reaction between an acid and an alkali producing water and a salt.
- Salt: A compound formed when a metal replaces hydrogen in an acid.
- Thermal Decomposition: A reaction where a single compound breaks down into two or more products when heated.
Common Confusions
- Confusing the type of salt formed with different acids.
- Mixing up the products of reactions with metal oxides and carbonates.
Typical Exam Questions
- What is formed when hydrochloric acid reacts with sodium hydroxide? Sodium chloride and water.
- What are the products when sulfuric acid reacts with copper oxide? Copper sulfate and water.
- What happens when copper carbonate is heated? It decomposes into copper oxide and carbon dioxide.
What Examiners Usually Test
- Understanding of neutralisation reactions.
- Ability to predict products of acid reactions with metal oxides and carbonates.
- Knowledge of the process and products of thermal decomposition.