AQA GCSE Trilogy Chemistry Paper 1 Higher June 2018 question paper 8464/C/1H

This question is about electrolysis. A student investigates the mass of copper produced during electrolysis of copper chloride solution. Figure 1 shows the apparatus.

Which gas is produced at the positive electrode (anode)? Tick one box.

02

Copper is produced at the negative electrode (cathode). What does this tell you about the reactivity of copper? Tick one box.

Table 1 shows the student’s results.

Determine the mean mass of copper produced after 3 minutes.

Calculate the mass X of copper produced in Experiment 2 after 5 minutes. Use Table 1 on page 3

The copper chloride solution used in the investigation contained 300 grams per dm³ of solid CuCl₂ dissolved in 1 dm³ of water. The student used 50 cm³ of copper chloride solution in each experiment. Calculate the mass of solid copper chloride used in each experiment.

This question is about sodium and chlorine. Figure 2 shows the positions of sodium and chlorine in the periodic table.

State one difference and one similarity in the electronic structure of sodium and of chlorine.

Sodium atoms react with chlorine atoms to produce sodium chloride (NaCl). Describe what happens when a sodium atom reacts with a chlorine atom. Write about electron transfer in your answer.

The reaction between sodium and chlorine is an exothermic reaction. Complete the reaction profile for the reaction between sodium and chlorine.

A student plans a method to prepare pure crystals of copper sulfate. The student’s method is:

1. Add one spatula of calcium carbonate to dilute hydrochloric acid in a beaker.

2. When the fizzing stops, heat the solution with a Bunsen burner until all the liquid is gone.

The method contains several errors and does not produce copper sulfate crystals. Explain the improvements the student should make to the method so that pure crystals of copper sulfate are produced.

This question is about the halogens.

Write the state symbol for chlorine at room temperature.

Figure 4 represents one molecule of fluorine. Complete the dot and cross diagram on Figure 4 You should show only the electrons in the outer shells.

19 A fluorine atom can be represented as 9 F What is the total number of electrons in a fluorine molecule (F₂)? Tick one box.

Aluminium reacts with bromine to produce aluminium bromide. Complete the balanced chemical equation for this reaction.

When chlorine reacts with potassium bromide, chlorine displaces bromine.

Explain why chlorine is more reactive than bromine.

This question is about structure and bonding.

Figure 5 shows part of the structure and bonding in diamond.

Explain why diamond has a high melting point.

Figure 6 shows part of the structure and bonding in sodium chloride (NaCl).

Explain the conditions needed for sodium chloride to conduct electricity.

Figure 7 shows the structure of sodium.

Describe how sodium conducts thermal energy.

Group 2 metal carbonates thermally decompose to produce a metal oxide and a gas.

Give the formula of each product when calcium carbonate (CaCO₃) is heated.

The relative formula mass (M_r) of a Group 2 metal carbonate is 197 Relative atomic masses (A_r): C = 12 O = 16 Calculate the relative atomic mass (A_r) of the Group 2 metal in the metal carbonate. Name the Group 2 metal.

Figure 8 shows the volume of gas produced when a different Group 2 carbonate, W, is heated.

Calculate the gradient of the line in Figure 8 Give the unit.

24 dm³ of gas is produced when one mole of a Group 2 carbonate is heated. Determine the relative formula mass of the Group 2 carbonate W. Use Figure 8

A scientist does two tests on four white solids. The solids are labelled A, B, C and D Test 1 Adds the sample of the solid to distilled water and stirs. Test 2 Measures the pH of the solution after Test 1 Table 2 shows the results.

These four solids are:

• magnesium oxide

• phosphorus oxide

• silicon dioxide

• sodium oxide.

Table 3 shows the solubility of these four solids in water.

Identify the solids A, B, C and D. Explain your answers.

10 cm³ of solution B is added to a beaker. Distilled water is added to the beaker until the final volume in the beaker is 1000 cm³ The pH of the solution is measured before and after distilled water is added. Table 4 shows the results.

Calculate the value of X.

This question is about iron. Iron reacts with dilute hydrochloric acid to produce iron chloride solution and one other product.

Name the other product.

Suggest how any unreacted iron can be separated from the mixture.

Magnesium reacts with iron chloride solution.

0.120 g of magnesium reacts with excess iron chloride solution. Relative atomic masses (A_r): Mg = 24 Fe = 56 Calculate the mass of iron produced, in mg

Explain which species is reduced in the reaction between magnesium and iron chloride.

Your answer should include the half equation for the reduction.