Question 1: Carbonates are chemical compounds containing the carbonate ion (CO₃²⁻). They are commonly found in minerals and are tested using acids to produce carbon dioxide gas.

Answer: Carbonates are compounds containing the carbonate ion (CO₃²⁻), tested with acids to produce CO₂ gas.

Question 1: Describe the chemical reaction that occurs when a carbonate reacts with an acid.

Answer: The carbonate reacts with acid to produce carbon dioxide gas, water, and a salt: carbonate + acid → salt + CO₂ + H₂O.

Question 2: Why is carbon dioxide gas important in identifying carbonates in a laboratory test?

Answer: CO₂ gas confirms the presence of carbonate ions because it is a direct product of the reaction between carbonate and acid.

Question 1: Calculate the amount of carbon dioxide (in grams) produced when 10 grams of calcium carbonate (CaCO₃) reacts completely with hydrochloric acid. (Molecular weight of CaCO₃ = 100 g/mol, CO₂ = 44 g/mol)

Answer: 0.44 grams

Question 1: Describe the steps involved in testing a mineral suspected to be a carbonate mineral in a laboratory setting.

Answer: First, place a small piece of the mineral in a test tube. Add dilute hydrochloric acid carefully. Observe for bubbling of CO₂ gas. Confirm the presence of carbonate if bubbles are produced. Collect the gas in a test tube over water for further analysis.

Question 2: Identify two safety precautions that should be taken during carbonate testing with acids.

Answer: Wear safety goggles and handle acids with care to prevent spills and skin contact.

Question 1: A mineral sample reacts vigorously with dilute hydrochloric acid, producing visible bubbling. What does this indicate about the mineral's composition?

Answer: It indicates that the mineral is likely a carbonate, as it produces CO₂ gas upon reaction with acid.

Question 1: Explain why carbonates react with acids to produce carbon dioxide gas. Include the chemical reaction in your answer. (6 marks)

Answer: Carbonates react with acids because the acid provides H⁺ ions that react with the carbonate ion (CO₃²⁻). This reaction produces carbonic acid, which decomposes into carbon dioxide gas (CO₂), water, and a salt. The reaction is: CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O.

Question 1: Describe how the reaction of carbonates with acids is utilized in industry or daily life.

Answer: In industry, carbonates are used in neutralizing acids in processes like water treatment and in the production of lime for construction. In daily life, baking soda (a carbonate) reacts with acids in recipes to produce CO₂, which causes dough to rise.