AQA GCSE Trilogy Chemistry Paper 1 Higher June 2023 question paper 8464/C/1H

This question is about carbon dioxide.

Carbon dioxide is soluble in water and forms an acidic solution.

Which ion makes the solution acidic?

Name an indicator that could be used to test if the solution is acidic. Give the result of the test.

Figure 1 shows the mass of carbon dioxide that will dissolve in 1 dm³ of water

at different temperatures.

How does the solubility of carbon dioxide change as the temperature of the

Tick (✓) one box.

Carbon dioxide dissolves in water to form an acidic solution. How does the pH of the solution change as the temperature of the water increases?

Tick (✓) one box.

Calcium carbonate reacts with hydrochloric acid to produce carbon dioxide. The equation for the reaction is:

What is the state symbol (x) in the equation? Tick (✓) one box.

Figure 2 shows equipment a student used for an investigation.

The student investigated the volume of carbon dioxide produced when different

masses of calcium carbonate react with hydrochloric acid. Describe a method the student could use.

Lithium hydroxide reacts with sulfuric acid to produce lithium sulfate. The equation for the reaction is:

What type of reaction is this?

Relative atomic masses (A_r): H = 1 O = 16 S = 32

Relative atomic mass (A_r): O = 16

Give your answer to 2 significant figures.

A solution of lithium sulfate contains 0.30 g of lithium sulfate in 25 cm³. Calculate the concentration of lithium sulfate in g/dm³.

Sodium is in Group 1 of the periodic table. Sodium reacts with oxygen to produce sodium oxide.

Balance the equation for the reaction.

Explain what happens to sodium atoms and to oxygen atoms when sodium reacts with oxygen to produce sodium oxide (Na₂O). Answer in terms of electrons.

Sodium burns in a gas jar of oxygen. Figure 3 shows the apparatus.

Give two observations seen during the reaction.

Describe two differences in the observations if potassium is used instead of sodium.

Group 7 elements are known as the halogens. All atoms of Group 7 elements contain protons, neutrons and electrons.

What is the order of discovery of the proton, neutron and electron? Tick (✓) one box.

Table 1 shows the mass of a proton and of an electron.

Calculate how many times heavier a proton is than an electron.

A bromine atom can be represented as⁸¹₃₅Br.

What is the number of neutrons in this bromine atom?

What is the number of electrons in a bromide ion ?

Chlorine has two isotopes. Table 2 shows the percentage abundance of the two isotopes of chlorine.

Calculate the relative atomic mass (A_r) of chlorine.

Figure 4 shows the outer shells in one molecule of chlorine (Cl₂). Complete the dot and cross diagram to show the electrons in the outer shells.

During electrolysis ions are discharged at the electrodes to produce elements. A student investigates the electrolysis of sodium chloride.

Sodium chloride solution conducts electricity. Complete the sentence.

Figure 5 shows the apparatus for the electrolysis of sodium chloride solution.

Suggest an element that could be used to make the inert electrodes.

Complete the half equation for the production of chlorine (Cl₂) at the positive electrode.

Sodium chloride solution has a pH of 7 During the electrolysis of sodium chloride solution:

• hydrogen gas is produced at the negative electrode

• the pH of the solution increases.

Explain why.

Acids react with some metals to produce soluble salts. A student adds magnesium to hydrochloric acid until no more acid reacts and

The equation for the reaction is:

The reaction between magnesium and hydrochloric acid is a redox reaction. Explain what happens to the magnesium atoms in this reaction.

0.72 g of magnesium is added to 100 cm³ of hydrochloric acid. The hydrochloric acid is in excess. Calculate the concentration of the magnesium chloride (MgCl₂) solution produced

This question is about structure and properties.

Which pair of substances both contain atoms in hexagonal rings? Tick (✓) one box.

Explain why the structure of copper allows the conduction of thermal energy.

Explain why copper oxide (CuO) has a high melting point.

Explain why water (H₂O) has a low melting point.