Edexcel GCSE Chemistry Paper 1 Higher June 2024 question paper 1CH0/1H

Chemical cells produce a voltage.

A chemical cell can be made by placing the metals copper and iron in a beaker of sodium chloride solution as shown in Figure 1.

Describe what will happen to the reading on the voltmeter over a long period of time.

Iron is a transition metal.

Which of the following is most likely to be a property of iron?

An iron atom has a diameter of 2.5210^–10 m.

What is the size of this iron atom in nanometres?

Figure 2 shows the arrangement of atoms in three different alloys of copper and

Explain which of the three alloys, A, B and C, is the strongest.

Barium hydroxide reacts with dilute hydrochloric acid to form barium chloride solution and water.

Complete the balanced equation for the reaction by adding a number in front of HC l (aq).

State what you would see during the reaction.

A student investigated how the pH of the mixture changed as barium hydroxide was added to dilute hydrochloric acid.

The student used this method.

step 1 measure out 50 cm3³ of dilute hydrochloric acid into a beaker using a measuring cylinder

step 2 use a glass rod to place a drop of the acid onto a piece of universal indicator paper and record the pH

step 3 add one spatula measure of barium hydroxide to the acid in the beaker and stir

step 4 use the glass rod to place a drop of the mixture onto a new piece of universal indicator paper and record the pH again

step 5 repeat steps 3 and 4 until there is no further change in the pH.

Name a piece of equipment that could be used to measure the pH of a substance more accurately than universal indicator paper.

Explain why, in step 3, the mixture was stirred after adding the barium hydroxide.

Figure 3 shows the student’s results.

Plot a graph of the pH of the mixture against the number of spatula measures of barium hydroxide.

Use the graph to find the pH of the mixture when 4.5 spatula measures of barium hydroxide are added.

Sodium carbonate has the formula Na₂CO₃.

Sodium carbonate contains Na⁺ ions and CO₃^2– ions.

The atomic number of sodium is 11.

What is the electronic configuration of the Na⁺ ion?

Explain why solid sodium carbonate cannot conduct electricity but a solution of sodium carbonate can conduct electricity.

Calculate the percentage by mass of sodium in sodium carbonate, Na₂CO₃.

(relative atomic masses: C = 12, O = 16, Na = 23)

percentage by mass of sodium =_........

Titanium can be extracted from titanium oxide, TiO₂, by reaction with magnesium.

100 tonnes of titanium oxide was heated with magnesium. The titanium formed in the reaction was separated and purified. The mass of titanium was then determined.

The results are shown in Figure 4.

Use the information in Figure 4 to calculate the percentage yield of titanium in this process.

Give your answer to 1 decimal place.

percentage yield =_........

Give two reasons why the percentage yield for this process is less than 100%.

The balanced equation for this process is

Calculate the atom economy of this process to produce titanium.

Give your answer to 2 significant figures.

(relative atomic masses: O = 16, Mg = 24, Ti = 48)

atom economy =_........

Ethanol, C₂H₅OH, can be produced by two different methods.

• by the hydration of ethene, C₂H₄

• and by the fermentation of a carbohydrate, e.g. sucrose, C₁₂H₂₂O₁₁

State why the hydration of ethene has an atom economy of 100%.

Explain how the atom economy of the fermentation reaction can be improved.

This question is about the extraction of metals.

Give two advantages of obtaining metals by recycling rather than by extracting them from their metal ores.

Small amounts of some metals are extracted using displacement reactions.

In one process, zinc dust is used to precipitate cadmium metal from a solution containing cadmium ions.

cadmium ions cadmium

Explain why this displacement reaction can be described as a redox reaction.

The formula of the cadmium ion is Cd²⁺. The formula of the phosphate ion is PO₄^3–.

Which is the formula of cadmium phosphate?

One of the alternative biological methods of extracting metals from very low‑grade ores is bioleaching using bacteria.

Give one disadvantage of this method of extracting metals from low‑grade ores.

Lead is low in the reactivity series.

Describe how to obtain a sample of lead from some lead oxide in the laboratory.

Titration can be used to find the volume of dilute hydrochloric acid needed to neutralise 25.0 cm³ of barium hydroxide solution.

Before the titration is carried out, the pipette and conical flask are rinsed out with pure water.

Explain the effect, if any, that traces of water in the pipette and conical flask after rinsing could have on the titration result.

pipette

conical flask

In the titration, a few drops of phenolphthalein indicator are added to the barium hydroxide solution.

State the change in colour of phenolphthalein at the end point, when the barium hydroxide solution has just been neutralised.

Write the ionic equation for the neutralisation reaction that occurs when hydrochloric acid is added to barium hydroxide solution.

When barium hydroxide solution is neutralised by dilute sulfuric acid, a white precipitate of barium sulfate is formed in the conical flask.

Describe an experiment to obtain a sample of pure, dry barium sulfate from the contents of the conical flask.

Water, acidified with dilute sulfuric acid, was electrolysed for 10 minutes using inert electrodes.

Figure 5 shows the apparatus used.

In this electrolysis, the acidified water is an electrolyte.

Explain why acidified water is an electrolyte.

Hydrogen collects at the negative electrode and oxygen collects at the positive electrode.

Which of these shows the results after 10 minutes of this electrolysis?

Complete and balance the half equation for the formation of oxygen at the positive electrode in this electrolysis.

Copper sulfate solution was electrolysed for 10 minutes using copper electrodes.

Figure 6 shows the mass of the cathode and the appearance of the copper sulfate solution before electrolysis and after electrolysis.

Describe what should be done to the copper cathode, after it has been removed from the copper sulfate solution, before its final mass is determined.

Explain, in terms of ions, the change in mass of the cathode shown in Figure 6.

Explain why the appearance of the copper sulfate solution did not change during the electrolysis.

This question is about the properties of different substances.

Silicon tetrachloride is a simple molecular covalent compound.

A molecule of silicon tetrachloride is composed of a silicon atom and four chlorine atoms.

• a silicon atom has 4 outer electrons

• a chlorine atom has 7 outer electrons

Draw a dot and cross diagram of a molecule of silicon tetrachloride, SiCl₄.

Show outer electrons only.

Explain why simple molecular covalent compounds such as silicon tetrachloride have low melting and boiling points.

Part of the structure of rubidium bromide is shown in Figure 7.

Which row shows the most likely melting point and boiling point of rubidium bromide?

*(c) Diamond and graphite are two forms of carbon.

Figure 8 shows how the carbon atoms are arranged in a part of the structure of each of these forms of carbon.

• diamond is one of the hardest known substances on Earth and is used in cutting tools.

• graphite is soft and flaky.

• diamond is a poor electrical conductor, but graphite is a good electrical conductor.

Explain, in terms of structure and bonding, these properties of diamond and graphite.

An investigation was carried out on the reactivity of four metals, D, E, F and G.

Equal sized pieces of these metals were placed in excess dilute hydrochloric acid and left for three minutes.

Figure 9 shows the observations of the reactions for metals D, E and F.

The order of reactivity for these metals is shown in Figure 10.

most reactive least reactive

Figure 10

Use the information in Figure 9 and Figure 10 to suggest the observations that would be made for metal G.

The dilute hydrochloric acid used in this reaction is a strong acid.

Explain the meaning of the terms dilute and strong acid.

dilute

strong acid

The formula of lead ethanoate is Pb(CH₃COO)₂.

Calculate the number of atoms that combine together to form 16.25 g of lead ethanoate.

(relative atomic masses: H = 1.00, C = 12.0, O = 16.0, Pb = 207

Avogadro number = 6.02×10²³)

number of atoms =_........

Iron is more reactive than copper.

Iron will displace copper from copper nitrate solution. Two possible balanced equations for the reaction are

It was found that 2.24 g of iron reacted with excess copper nitrate solution to form 3.81 g of copper.

Carry out a calculation, using the information above, to show which equation represents the reaction taking place.

(relative atomic masses: Fe = 56.0, Cu = 63.5)

Hydrogen can be produced by the reaction of methane with steam.

Methane reacts with steam in the presence of a nickel catalyst to produce hydrogen and a dynamic equilibrium is reached.

The equation for this equilibrium reaction is

methane

The forward reaction takes in heat energy and is endothermic.

Describe the effect of the catalyst on the rate of attainment of equilibrium and on the equilibrium yield of products.

*(ii) A manufacturer produces hydrogen by the reaction of methane with steam in the presence of a nickel catalyst using the conditions

pressure 20 atmospheres

Explain what effect there would be on the rate of attainment of equilibrium and the equilibrium yield of hydrogen if the manufacturer were to use a higher temperature of 1000C at a lower pressure of 10 atmospheres without changing the catalyst.

Using the equation for the reaction

calculate the maximum volume of products, in dm³, that could be formed by the complete reaction of 650 dm³ of methane.

(assume all volumes of gases are measured under the same conditions of temperature and pressure)

maximum volume of products =_........

Using the same equation for the reaction

calculate the maximum mass, in g, of carbon dioxide for every 1800 dm³ of hydrogen, measured at room temperature and pressure, produced in this reaction.

(relative formula mass: CO₂ = 44; 1 mol of any gas at room temperature and pressure occupies 24 dm³)

mass of carbon dioxide =_........