AQA GCSE Trilogy Chemistry Paper 1 Higher November 2021 question paper 8464/C/1H

This question is about the periodic table.

Figure 1 shows part of Mendeleev’s version of the periodic table.

Which group of elements had not been discovered when Mendeleev’s version of the periodic table was published?

Figure 2 represents different models of the atom.

Which model represents the plum pudding model? Tick (✓) one box.

Which model resulted from Chadwick’s experimental work? Tick (✓) one box.

Potassium has different isotopes.

What is meant by ‘isotopes’? You should refer to subatomic particles.

Table 1 shows the mass numbers and the percentage abundance of two isotopes of potassium.

Calculate the relative atomic mass (A_r) of potassium. Give your answer to 1 decimal place.

Acids react to produce salts. Universal indicator is added to water and then nitric acid is added to the mixture.

Give the colour change when nitric acid is added to the mixture of universal indicator and water. Tick (✓) one box.

What happens to the pH of water when nitric acid is added? Tick (✓) one box.

What is the state symbol for nitric acid?

Zinc carbonate reacts with nitric acid.

The word equation for the reaction is: zinc carbonate + nitric acid → zinc nitrate + water + carbon dioxide white solid colourless solution

Give two observations that would be made when zinc carbonate is added to nitric acid until the zinc carbonate is in excess.

The formula of the zinc ion is Zn²⁺ The formula of the nitrate ion is NO₃^– What is the formula for zinc nitrate? Tick (✓) one box.

Acids react with insoluble metal oxides to produce salts. Plan a method to produce a pure, dry sample of the soluble salt copper chloride from an acid and a metal oxide.

This question is about energy change. A student investigated the temperature change when 10 g of ammonium nitrate was

This is the method used.

1. Measure the temperature of 100 cm³ of water.

2. Add 10 g of ammonium nitrate.

3. Stir once.

4. Measure the temperature of the solution every minute for 7 minutes.

Figure 3 shows the apparatus.

What is the dependent variable in this investigation?

Give three improvements to the investigation to make the results more accurate.

Figure 4 shows the results.

Explain the results.

Draw a reaction profile for an exothermic reaction. You should label:

• the energy level of the reactants and of the products

• the activation energy

• the overall energy change.

Carbon can exist in a number of different structures.

The first fullerene to be discovered was Buckminsterfullerene. What is the formula of Buckminsterfullerene? Tick (✓) one box.

Graphite is a form of carbon. Explain why graphite conducts electricity.

Steel is an alloy of iron and carbon.

Explain why steel is harder than iron.

Iron is alloyed with carbon and other metals to make stainless steel. A stainless steel fork contains 71.92% iron. Table 2 shows the mass of each element in the fork.

Calculate the mass of iron (X) in the fork.

This question is about the electrolysis of aqueous solutions.

Hydrogen gas and chlorine gas are produced when sodium chloride solution is electrolysed.

Hydrogen ions (H⁺) are attracted to the negative electrode. The half equation for the reaction at the negative electrode is:

What type of reaction happens at the negative electrode? Give the reason for your answer.

Chloride ions are attracted to the positive electrode. Complete the half equation for the production of chlorine gas (Cl₂).

Hydrogen gas and oxygen gas are produced when sodium sulfate solution is electrolysed. Explain how oxygen gas is produced in the electrolysis of sodium sulfate solution.

Metal oxides are produced when metals are heated in air. A student investigated the change in mass when 0.12 g of magnesium was heated in air. Figure 5 shows the apparatus.

The student measured the mass of magnesium oxide produced.

0.12 g of magnesium reacted to produce 0.20 g of magnesium oxide. Calculate the number of moles of oxygen gas (O₂) that reacted. Relative atomic mass (A_r): O = 16

The student repeated the experiment without a lid on the crucible. Suggest why the mass of magnesium oxide produced would be different without a lid on the crucible.

Copper reacts with oxygen to produce copper oxide. 63.5 g of copper produces 79.5 g of copper oxide. Calculate the mass of copper oxide produced when 0.50 g of copper reacts with oxygen. Give your answer to 3 significant figures.

Iron reacts with oxygen to produce an oxide of iron. 0.015 moles of iron reacts with 0.010 moles of oxygen gas (O₂). Determine:

• the formula of the iron oxide produced

• the balanced symbol equation for the reaction.

Balanced symbol equation

Methane, ethane, propane and butane all react with oxygen to produce carbon dioxide and water.

Suggest why a mixture of methane and oxygen does not react at room temperature. Answer in terms of particles.

Table 3 shows the energy released when methane, ethane and propane react with oxygen to produce carbon dioxide and water.

Predict the energy released when butane (C₄H₁₀) reacts with oxygen to produce carbon dioxide and water.

Propane reacts with oxygen to produce carbon dioxide and water. The displayed formula equation for the reaction is:

The reaction is exothermic. In the reaction, the energy released when forming new bonds is 1640 kJ/mol greater than the energy needed when breaking bonds. Table 4 shows bond energies.

Calculate the C––C bond energy (X).