Question 1: Carbonates are salts of carbonic acid containing the carbonate ion (CO₃²⁻). They commonly react with acids to produce carbon dioxide gas. Describe the general reaction between a carbonate and an acid.

Answer: A carbonate reacts with an acid to produce a salt, water, and carbon dioxide gas.

Question 2: What is the chemical formula for the carbonate ion?

Answer: CO₃²⁻

Question 1: Describe a simple method to test whether a sample contains carbonate ions.

Answer: Add dilute acid to the sample; if carbon dioxide bubbles are produced, it contains carbonate ions.

Question 2: What safety precautions should be taken when handling dilute acids during carbonate tests?

Answer: Wear safety goggles and gloves, handle acids carefully, and work in a well-ventilated area.

Question 1: Write the word equation for the reaction of calcium carbonate with hydrochloric acid.

Answer: Calcium carbonate + Hydrochloric acid → Calcium chloride + Water + Carbon dioxide

Question 2: Explain why carbon dioxide is produced during this reaction.

Answer: Because the carbonate ion reacts with the acid to release CO₂ gas as a product.

Question 1: Calculate the volume of carbon dioxide produced at room temperature and pressure (RTP, 24°C, 1 atm) when 5.00 g of sodium carbonate (Na₂CO₃) reacts completely with hydrochloric acid. (Molar mass of Na₂CO₃ = 106 g/mol, molar volume of gas at RTP = 24 dm³/mol).

Answer: 12 dm³

Question 1: Design a simple experiment to test if a given rock sample contains carbonate minerals. Include the key variables and safety precautions.

Answer: Add dilute acid to the sample; observe for bubbling indicating CO₂ release. Variables include type of acid, amount of acid, and sample size. Safety precautions include wearing goggles and gloves, handling acids carefully, and working in a ventilated area.

Question 1: A sample of a mineral reacts with dilute hydrochloric acid to produce bubbles. When the gas is tested with limewater, it turns cloudy. Explain what this indicates about the mineral.

Answer: The mineral contains carbonate ions, as the reaction produces carbon dioxide which turns limewater cloudy.

Question 1: Explain why calcium carbonate is used as a building material and in antacids.

Answer: Calcium carbonate is a natural, abundant mineral that provides strength and durability in buildings. It neutralises excess stomach acid, making it effective in antacids.

Question 1: In your own words, explain why the reaction of carbonates with acids is significant in both laboratory and industrial contexts.

Answer: The reaction helps identify carbonate minerals, analyse rock samples, and is fundamental in manufacturing processes such as producing lime, cement, and neutralising acids in various industries. It also demonstrates key concepts of chemical reactions and gas evolution.