AQA GCSE Trilogy Chemistry Paper 1 Foundation June 2025 question paper 8464/C/1F

This question is about atoms and ions.

The model of the atom has changed over time.

In an early model, scientists thought the atom was a tiny sphere that could not be divided.

Figure 1 represents this early model of the atom.

The discovery of a subatomic particle led to a change in the model in Figure 1.

Which was the first subatomic particle to be discovered?

Tick () one box.

In a later model of the atom, most of the mass was concentrated in the centre of the atom.

What is the name of the centre of an atom?

Atoms contain three types of subatomic particle.

Draw one line from each subatomic particle to the relative charge of the particle.

What is meant by the ‘atomic number of an atom’?

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Table 1 shows information about two isotopes of an element.

Calculate the relative atomic mass (A_r) of the element.

Use the equation:

A = (mass number × percentage) of isotope A + (mass number × percentage) of isotope B

Give your answer to 1 decimal place.

An oxygen atom has eight electrons.

Complete Figure 2 to show the electronic structure of an oxygen atom.

Figure 2

Figure 3 represents two models of sodium chloride.

What are two advantages of model B compared with model A ?

Tick () two boxes.

Lithium, carbon, nitrogen, fluorine and neon are elements in the same row of the periodic table.

What is the chemical symbol of lithium?

Use the periodic table.

Lithium has metallic bonding.

Which electrons are involved in metallic bonding?

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Lithium reacts with fluorine to produce lithium fluoride.

Draw one line from each substance to the particle diagram that represents the substance.

Table 2 shows the electrical conductivity of three substances.

Lithium fluoride is an ionic compound.

Which substance is lithium fluoride?

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Carbon can exist in different forms.

Figure 4 represents one form of carbon.

What is the name of the form of carbon in Figure 4 ?

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Carbon and fluorine form a compound with the formula CF₄

Calculate the relative formula mass (M_r) of CF₄

Relative atomic masses (A_r): C = 12 F = 19

Figure 5 represents a molecule of nitrogen.

What is the total number of shared electrons in the covalent bond shown in Figure 5 ?

Lithium and nitrogen form a compound with the formula Li₃N

Complete the sentence.

Choose the answer from the box.

Neon does not react with other elements to form compounds.

Why is neon unreactive?

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A student investigated the reaction of magnesium with oxygen.

Figure 6 shows the apparatus.

This is the method used.

1. Measure the mass of an empty crucible.

2. Add 0.10 g of magnesium to the crucible.

3. Heat the crucible and contents for 5 minutes.

4. Allow to cool and measure the mass of the crucible and contents.

5. Repeat steps 1 to 4 using different masses of magnesium.

Complete the word equation for the reaction.

magnesium + oxygen →

Complete the sentence.

Choose the answer from the box.

Table 3 shows the measurements for one of the experiments.

Calculate the mass of magnesium in the crucible before heating.

Why does the reaction result in an increase in the mass of the contents of the crucible?

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The student determined the mass of the contents of the crucible after heating each mass of magnesium.

Figure 7 shows the results.

Draw a ring around the anomalous result in Figure 7.

The student did the experiment using 0.60 g of magnesium four times.

Table 4 shows the results.

Calculate mean value X.

The student used a Bunsen burner instead of a water bath to heat the crucible.

Why did the student use a Bunsen burner?

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A different student did the investigation.

The student heated the crucible for 1 minute instead of for 5 minutes.

The student obtained different results.

Suggest one reason why the student obtained different results.

This question is about metals.

Complete the sentence.

Choose the answer from the box.

Iron is extracted from iron oxide by reduction with carbon.

Why is iron extracted by reduction with carbon?

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Aluminium is extracted by the electrolysis of aluminium oxide.

Figure 8 shows the apparatus used to extract aluminium.

The mixture of aluminium oxide and cryolite has a lower melting point than aluminium oxide alone.

Why is the melting point lowered?

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After some time, the positive electrodes need to be replaced.

Why must the positive electrodes be replaced?

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Aluminium can be mixed with other metals to form alloys.

How does the hardness of an alloy of aluminium compare with the hardness of pure aluminium?

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Aluminium can form an alloy with silver.

Figure 9 shows how the melting point of the alloy changes with the percentage (%) of silver in the mixture.

Describe how the melting point of the alloy changes as the percentage of silver in the mixture increases.

Use data from Figure 9.

This question is about acids.

A student investigated the volume of an alkali needed to react completely with

Figure 10 shows the apparatus.

This is the method used.

1. Add 25 cm³ of the acid to a beaker.

2. Add a piece of universal indicator paper to the acid.

3. Add the alkali drop by drop to the acid until the universal indicator paper changes colour to green.

4. Record the number of drops of alkali added.

The method does not give an accurate volume of alkali needed to react completely with the acid.

Suggest two improvements to the method.

What is the pH of the solution when the universal indicator paper turns green?

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What name is given to the reaction between an acid and an alkali?

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Which ion do all acids contain?

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Name the acid that reacts with sodium hydroxide to produce sodium nitrate.

Figure 11 shows a reaction profile for the reaction between an acid and an alkali.

What do labels A and B represent on Figure 11 ?

Choose the answers from the box.

Acids also react with insoluble solid substances to produce salt solutions.

When making a salt solution, excess solid is added to the acid.

Draw the apparatus used to separate the excess solid from the salt solution by filtration.

The apparatus should collect:

• the excess solid

• the salt solution.

Solid X reacts with hydrochloric acid to produce zinc chloride and hydrogen gas.

Name solid X.

A teacher demonstrated the electrolysis of copper chloride solution.

Figure 12 shows the apparatus.

The teacher measured the mass of the negative electrode every 60 seconds.

Chlorine gas is given off during the electrolysis of copper chloride solution.

Chlorine gas is poisonous.

Give one way of reducing the risk of harm.

Table 5 shows the results.

Plot the data from Table 5 on Figure 13.

Draw a line of best fit.

The first point has been plotted for you.

A student made the hypothesis:

‘The negative electrode will increase by a constant mass every 60 seconds.’

How do the results in Table 5 show that the hypothesis is not correct?

25 cm³ of the solution of copper chloride contained 5.5 g of copper chloride.

Calculate the concentration of the solution in g/dm³.

The teacher also electrolysed potassium chloride solution.

Hydrogen gas was given off at the negative electrode.

Why was hydrogen gas given off?

Tick () one box.

A student investigated an exothermic reaction.

The student reacted solid calcium oxide with water to produce calcium hydroxide.

What is meant by an ‘exothermic’ reaction?

The formula of calcium hydroxide is Ca(OH)₂

Calculate the percentage by mass of oxygen in calcium hydroxide.

Relative atomic mass (A_r): O = 16

Relative formula mass (M_r): Ca(OH)₂ = 74

When solid calcium oxide is added to water, the temperature of the reaction mixture changes.

Plan a method to investigate how changing the mass of calcium oxide affects the temperature change of the reaction mixture.