1.1 The fundamental ideas in chemistry
Group 1 elements burn vigorously when heated in oxygen.
(a) Complete these diagrams to show the electronic structures of sodium and oxygen atoms. (2 marks)
(b) Write the word equation that describes the reaction between sodium and oxygen. (1 mark)
(c) Write the balanced equation for this reaction, including the state symbols. (3 marks)
(d) Why are the elements in group 0 unreactive? (1 mark)
1.2 Limestone and building materials
When limestone is heated to make cement it first reacts to produce lime (calcium oxide).
(a) Write a word equation using chemical names for what happens when limestone is heated. (1 mark)
(b) Write the chemical formula for:
(i) limestone (1 mark)
(ii) lime (1 mark)
(c) Write a balanced equation with state symbols for what happens when limestone is heated. (2 marks)
Water reacts with lime to form slaked lime (calcium hydroxide).
(d) Write a word equation for this reaction using chemical names. (1 mark)
(e) Write a balanced equation with state symbols for this reaction. (3 marks)
(f) Farmers use slaked lime for liming the soil. Why is it necessary to lime some soils? (1 mark)
1.3 Metals and their uses
Copper can be obtained from solutions of copper salts by electrolysis or by displacement using scrap iron. It can also be extracted by phytomining.
(a) Draw an arrow on the following reactivity series (reactivity decreases down the list) to show where copper should be placed. (1 mark)
(b) Write a word equation for the displacement of copper from copper sulfate solution by iron. (1 mark)
(c) Write a balanced equation with state symbols for this reaction. (3 marks)
(d) Explain why copper is produced at the negative electrode during electrolysis.
(e) What is phytomining? (2 marks)
(f) Predict the method of extraction used to...