AQA GCSE Chemistry Paper 1 Higher June 2018 question paper 8462/1H

Soluble salts are formed by reacting metal oxides with acids.

Give one other type of substance that can react with an acid to form a soluble salt.

Calcium nitrate contains the ions Ca²⁺ and NO₃^– Give the formula of calcium nitrate.

Describe a method to make pure, dry crystals of magnesium sulfate from a metal oxide and a dilute acid.

This question is about metals and metal compounds.

Iron pyrites is an ionic compound. Figure 1 shows a structure for iron pyrites.

Determine the formula of iron pyrites. Use Figure 1.

An atom of iron is represented as⁵⁶₂₆Fe Give the number of protons, neutrons and electrons in this atom of iron.

Iron is a transition metal. Sodium is a Group 1 metal. Give two differences between the properties of iron and sodium.

Nickel is extracted from nickel oxide by reduction with carbon.

Explain why carbon can be used to extract nickel from nickel oxide.

An equation for the reaction is:

Calculate the percentage atom economy for the reaction to produce nickel. Relative atomic masses (A_r): C = 12 Ni = 59 Relative formula mass (M_r): NiO = 75 Give your answer to 3 significant figures.

Chemical reactions can produce electricity.

Figure 2 shows a simple cell.

Which of these combinations would not give a zero reading on the voltmeter in Figure 2 ?

Tick one box. Electrode A Electrode B Electrolyte

Alkaline batteries are non-rechargeable.

Why do alkaline batteries eventually stop working?

Why can alkaline batteries not be recharged?

Hydrogen fuel cells and rechargeable lithium-ion batteries can be used to power electric cars.

Complete the balanced equation for the overall reaction in a hydrogen fuel cell.

Table 1 shows data about different ways to power electric cars.

Evaluate the use of hydrogen fuel cells compared with rechargeable lithium-ion batteries to power electric cars. Use Table 1 and your own knowledge.

Figure 3 represents different models of the atom.

Which diagram shows the plum pudding model of the atom?

Tick one box.

Which diagram shows the model of the atom developed from the alpha particle scattering experiment?

Tick one box.

Which diagram shows the model of the atom resulting from Bohr’s work?

Tick one box.

Define the mass number of an atom.

Element X has two isotopes. Their mass numbers are 69 and 71 The percentage abundance of each isotope is:

Estimate the relative atomic mass of element X. Tick one box.

Chadwick’s experimental work on the atom led to a better understanding of isotopes. Explain how his work led to this understanding.

A student investigated the temperature change in displacement reactions between metals and copper sulfate solution. Table 2 shows the student’s results.

Plot the data from Table 2 on Figure 4 as a bar chart.

The student concluded that the reactions between the metals and copper sulfate solution are endothermic. Give one reason why this conclusion is not correct.

The temperature change depends on the reactivity of the metal. The student’s results are used to place copper, iron, magnesium and zinc in order of their reactivity. Describe a method to find the position of an unknown metal in this reactivity series. Your method should give valid results.

Draw a fully labelled reaction profile for the reaction between zinc and copper sulfate solution on Figure 5.

A student investigated the electrolysis of different substances. Figure 6 shows the apparatus.

Explain why electrolysis would not take place in the apparatus shown in Figure 6.

Explain why graphite conducts electricity. Answer in terms of the structure and bonding in graphite.

The student investigated how the volume of gases produced changes with time in the electrolysis of sodium chloride solution. Figure 7 shows the apparatus.

The student made an error in selecting the apparatus for this investigation. How should the apparatus be changed? Give one reason for your answer.

Another student used the correct apparatus. This student measured the volumes of gases collected every minute for 20 minutes. Figure 8 shows the student’s results.

Describe the trends shown in the results. Use values from Figure 8.

The number of moles of each gas produced at the electrodes is the same. No gas escapes from the apparatus. Suggest one reason for the difference in volume of each gas collected.

Calculate the amount in moles of chlorine collected after 20 minutes. Use Figure 8. The volume of one mole of any gas at room temperature and pressure is 24.0 dm³ Give your answer in standard form.

This question is about Group 7 elements. Chlorine is more reactive than iodine.

Name the products formed when chlorine solution reacts with potassium iodide solution.

Explain why chlorine is more reactive than iodine.

Chlorine reacts with hydrogen to form hydrogen chloride. Explain why hydrogen chloride is a gas at room temperature. Answer in terms of structure and bonding.

Bromine reacts with methane in sunlight. Figure 9 shows the displayed formulae for the reaction of bromine with methane.

Table 3 shows the bond energies and the overall energy change in the reaction.

Calculate the bond energy X for the C^___Br bond. Use Figure 9 and Table 3.

Titanium is a transition metal. Titanium is extracted from titanium dioxide in a two stage industrial process. Stage 1 TiO₂ + 2 C + 2 Cl₂ TiCl₄ + 2 CO Stage 2 TiCl₄ + 4 Na Ti + 4 NaCl

Suggest one hazard associated with Stage 1.

Water must be kept away from the reaction in Stage 2. Give one reason why it would be hazardous if water came into contact with sodium.

Suggest why the reaction in Stage 2 is carried out in an atmosphere of argon and not in air.

Titanium chloride is a liquid at room temperature. Explain why you would not expect titanium chloride to be a liquid at room temperature.

In Stage 2, sodium displaces titanium from titanium chloride.

Sodium atoms are oxidised to sodium ions in this reaction. Why is this an oxidation reaction?

Complete the half equation for the oxidation reaction.

In Stage 2, 40 kg of titanium chloride was added to 20 kg of sodium. The equation for the reaction is:

Relative atomic masses (A_r): Na = 23 Cl = 35.5 Ti = 48 Explain why titanium chloride is the limiting reactant. You must show your working.

For a Stage 2 reaction the percentage yield was 92.3% The theoretical maximum mass of titanium produced in this batch was 13.5 kg. Calculate the actual mass of titanium produced.

This question is about acids and alkalis.

Dilute hydrochloric acid is a strong acid. Explain why an acid can be described as both strong and dilute.

A 1.0 10^–3 mol/dm³ solution of hydrochloric acid has a pH of 3.0 What is the pH of a 1.0 10^–5 mol/dm³ solution of hydrochloric acid?

A student titrated 25.0 cm³ portions of dilute sulfuric acid with a 0.105 mol/dm³ sodium hydroxide solution.

Table 4 shows the student’s results.

The equation for the reaction is:

Calculate the concentration of the sulfuric acid in mol/dm³ Use only the student’s concordant results. Concordant results are those within 0.10 cm³ of each other.

Explain why the student should use a pipette to measure the dilute sulfuric acid and a burette to measure the sodium hydroxide solution.

Calculate the mass of sodium hydroxide in 30.0 cm³ of a 0.105 mol/dm³ solution. Relative formula mass (M_r): NaOH = 40