Edexcel GCSE Chemistry Paper 1 Foundation November 2020 question paper 1CH0/1F

When solid sodium chloride is mixed with water, sodium chloride solution forms.

What name is given to the process of mixing a solid with water to form a solution?

Sodium reacts with hydrochloric acid to form sodium chloride and hydrogen.

Write the word equation for this reaction.

The hazard symbol shown in Figure 1 is used on containers of sodium.

What is the meaning of this hazard symbol?

Hydrogen has one electron in its electron shell. Figure 2 shows the incomplete dot and cross diagram of a hydrogen molecule.

Complete Figure 2 to show the electrons in the covalent bond between the two atoms of hydrogen.

The pH of a sodium chloride solution was measured.

State what could be used to measure the pH of a solution.

Sodium chloride solution is neutral.

Give the pH of this solution.

Chlorine has an atomic number of 17.

Figure 3 shows the arrangement of electrons in an atom of chlorine.

What is the electronic configuration of this atom?

Explain, using Figure 3, why chlorine belongs to group 7 of the periodic table.

The nucleus of an atom is made up of protons and neutrons. Atoms of chlorine contain 17 protons.

Figure 4 shows some information about a proton, a neutron and an electron.

Explain, using the information in Figure 3 and Figure 4, why atoms of chlorine have no overall charge.

Atoms of chlorine-37 have a mass number of 37.

Calculate the number of neutrons in atoms of chlorine-37.

number of neutrons =_........

There are two isotopes of chlorine, chlorine-35 and chlorine-37.

Explain the meaning of the term isotopes.

In industry, ammonia is manufactured by reacting nitrogen with hydrogen.

Give the name of the industrial process used to manufacture ammonia.

Write the word equation for this reaction, including the correct symbol to show that the reaction is reversible.

The formula of ammonia is NH₃.

State what the formula of ammonia shows about the number of nitrogen atoms and the number of hydrogen atoms combined in a molecule of ammonia.

Most of the ammonia manufactured in industry is used to produce fertilisers.

A fertiliser is made by reacting ammonia with nitric acid.

What is the name of this fertiliser?

Explain the importance of fertilisers in farming.

In the 19th century, Mendeleev arranged the elements known at the time to form his periodic table. Mendeleev’s periodic table is different from the modern periodic table.

State one difference between Mendeleev’s periodic table and the modern periodic table.

Aluminium oxide reacts with hydrochloric acid to form a salt and water.

State the name of the salt formed.

In this reaction aluminium oxide is a base.

State the type of reaction that takes place when an acid reacts with a base.

Gallium, Ga, is in the same group of the modern periodic table as aluminium.

The formula of aluminium oxide is Al₂O₃.

Predict the formula of gallium oxide.

Gallium oxide has a very high melting point. Gallium oxide does not conduct electricity when solid but does conduct electricity when molten.

What type of substance is gallium oxide?

Figure 5 shows the changes of state for gallium and the arrangement of particles in liquid gallium.

Complete the boxes for solid gallium and gaseous gallium by drawing the arrangement of the particles in each of these physical states.

Give the name of the change of state labelled Y in Figure 5.

Gallium metal is a conductor of electricity.

Explain how metals conduct electricity.

Transition metals have many uses.

The pie chart in Figure 6 shows the uses of one transition metal.

Calculate the percentage of this transition metal used in construction.

percentage of this transition metal used in construction =_........

Figure 7 shows five statements about iron.

Put ticks () in the boxes in Figure 7 to show which statements are true and which statements are false. The first one has been done for you.

Most iron produced is converted into alloys of iron.

State why alloys have more uses than pure metals.

An alloy of iron contains 0.40 % of molybdenum.

Calculate the mass of molybdenum contained in a 30 g sample of this alloy of iron.

mass of molybdenum =_........

Many transition metals are used to make the reactants in chemical cells.

Figure 8 shows a graph of the voltage produced by a chemical cell as it is used in a torch for many hours.

Suggest an explanation for the shape of the graph.

Some metals are found in the Earth’s crust as uncombined elements. Reactive metals are found in ores.

In ores, metals are combined with other elements.

Which of these metals is found as the uncombined element in the Earth’s crust?

Give two advantages of recycling metals rather than extracting metals from their ores.

An ore of iron is mostly iron oxide, Fe₂O₃. Iron can be extracted from this iron oxide by heating it with carbon.

Balance this equation for the reaction that takes place.

Most copper ores are described as low grade. This means that the percentage of copper in the ore is very small.

5000 kg of one copper ore was found to contain 42.5 kg of copper.

Calculate the percentage of copper in this ore.

percentage of copper in ore =_........

In one stage of the extraction of lead from its ore, lead oxide is heated strongly with carbon.

The equation for the reaction is

Explain, using this equation, which substance has been oxidised in this reaction.

A titanium ore was analysed and found to contain 12 g of titanium atoms combined with 8.0 g of oxygen atoms.

Calculate the empirical formula of this titanium compound. (relative atomic masses: Ti = 48, O = 16)

You must show your working.

empirical formula =_........

Iron rusts when it is left in certain conditions.

Figure 9 shows the apparatus used to investigate the rusting of some iron nails.

Explain why the iron nail in tube A would rust but the iron nails in tubes B and C would not rust.

Magnesium is more reactive than iron. Figure 10 shows an iron nail with a strip of magnesium wrapped around it, placed in some water. The tube was left for a few days.

State what would happen to this iron nail.

When iron rusts, a brown solid forms on the surface of the iron.

What happens to the iron as the rust forms?

Give one reason why metals are electroplated.

*(c) The pure metals aluminium, copper and gold and the alloys brass and magnalium are used to make many useful articles.

The way in which these metals and alloys are used is related to their properties, such as their density, electrical conductivity, resistance to corrosion and strength.

State some uses of aluminium, copper, gold, brass and magnalium and explain how each use is related to their properties.

Figure 11 shows the apparatus that can be used to electrolyse sodium sulfate solution using inert electrodes.

Hydrogen is produced at the negative electrode during electrolysis.

Describe the test to show the gas is hydrogen.

What is the name of gas X that forms at the positive electrode?

State what is meant by the term electrolysis.

The sodium sulfate solution was made by dissolving 28.4 g of sodium sulfate in water to make 250 cm³ of solution.

Calculate the concentration of this solution in g dm⁻³.

Give your answer to three significant figures.

concentration =_........ g dm

The ions present in sodium sulfate are

Write the formula of sodium sulfate using this information.

In Figure 11, the gases given off at the electrodes are collected in test-tubes. However, the actual volume of gases cannot be measured using these test-tubes.

Suggest what apparatus could be used in place of the test-tubes in Figure 11 to measure the volume of gases given off.

State what could be added into the circuit to show a current is flowing during electrolysis.

The word equation for the reaction between copper carbonate and dilute sulfuric acid is

copper sulfuric copper carbon

Complete the balanced equation for this reaction.

Calculate the relative formula mass of copper carbonate, CuCO₃. (relative atomic masses: C = 12.0, O = 16.0, Cu = 63.5)

relative formula mass of CuCO₃ =_........

What is the chemical test to show that a gas is carbon dioxide?

Figure 12 shows a conical flask containing dilute sulfuric acid. Copper carbonate is added to the acid in the flask. The copper carbonate is added one spatula measure at a time until the reaction has finished.

State two observations that would show the reaction has finished.

*(ii) Describe how you would obtain a solution of copper sulfate from the mixture and how you would obtain pure, dry copper sulfate crystals from this solution.

Your description should include the apparatus you would use.

You may wish to use diagrams in your answer.

Potassium hydroxide reacts with hydrochloric acid to form potassium chloride and water.

potassium hydroxide + hydrochloric acid potassium chloride + water

A student carried out a titration to find the exact volume of dilute hydrochloric acid that reacted with 25.0 cm³ of potassium hydroxide solution.

There were five steps in the titration. The steps shown are not in the correct order.

step J pour the potassium hydroxide solution into a conical flask and add a few drops of indicator to this solution step K fill a burette with the dilute hydrochloric acid and record the initial reading from the burette step L use a measuring cylinder to obtain 25 cm³ of potassium hydroxide solution step M take a final reading from the burette and calculate the volume of the dilute hydrochloric acid reacted step N run the dilute hydrochloric acid from the burette into the conical flask until the indicator changes colour

Write the steps in the correct order.

Some of the steps have been completed for you.

first step last step

Suggest an alternative piece of apparatus that could be used in step L to obtain exactly 25.0 cm³ of potassium hydroxide solution.

A student was then asked to produce a pure sample of solid potassium chloride.

After finding the volume of acid reacted in step M, the student added this volume of acid to a fresh 25.0 cm³ sample of the potassium hydroxide solution. This mixture was then evaporated.

Explain why this new mixture was evaporated rather than the original mixture from the titration, to produce a pure sample of solid potassium chloride.

After evaporation, the mass of the potassium chloride was determined.

The theoretical yield of the experiment was 0.70 g. The actual yield was 0.84 g.

This gave a percentage yield greater than 100%.

Calculate the percentage yield of this experiment.

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

Suggest a reason why the actual yield was greater than the theoretical yield.

The equation for the reaction between potassium hydroxide solution and dilute hydrochloric acid is

Calculate the atom economy for the production of potassium chloride from potassium hydroxide and hydrochloric acid. (relative formula masses: KOH = 56.0, HCl = 36.5, KCl = 74.5, H₂O = 18.0)

Give your answer to one decimal place.

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