Chemistry 0620 · IGCSE

Corrosion of metals

98 practice questions on Corrosion of metals, with worked solutions and instant marking.

One way to prevent iron from rusting is to stop oxygen from reaching the metal surface. Which rust prevention method does not depend on this approach?

Feb/March 2016

What substances are necessary for iron to rust?

Feb/March 2019

What methods can be used to prevent iron from rusting?

Feb/March 2020

Zinc is applied to iron as a protective coating to stop rusting. Why is zinc a suitable metal to use?

Feb/March 2020

What substances are needed for iron to rust?

Feb/March 2023

Iron rusts, whereas aluminium does not corrode easily. Which statement accounts for the fact that aluminium does not corrode easily?

Feb/March 2024

Steel bridges are coated with paint to reduce the chance of rust developing on their surfaces. What makes steel rust?

Feb/March 2025

One example of sacrificial protection is the attachment of zinc blocks to the outside of a ship’s steel hull. Which statement explains why zinc is chosen to protect the iron in the steel against rusting?

Feb/March 2025

When separate strips of aluminium foil and copper foil are heated in air, the copper foil reacts to form a black solid, whereas the aluminium foil does not react. Which statement accounts for these observations?

Feb/March 2025

The diagram illustrates an experiment designed to find out how paint influences the rusting of iron. What change occurs in the water level in tubes P and Q?

May/June 2016

The diagram illustrates an experiment used to find out how paint influences the rusting of iron. What change occurs to the water level in tubes P and Q?

May/June 2016

The diagram illustrates an experiment used to investigate the way paint affects the rusting of iron. What happens to the water level in tubes P and Q?

May/June 2016

The diagram illustrates an experiment used to investigate the effect of paint on the rusting of iron. What occurs to the water level in tubes P and Q?

May/June 2016

The diagram illustrates an experiment used to find out how paint influences the rusting of iron. Describe the change in water level in tubes P and Q.

May/June 2016

The diagram illustrates an experiment used to study how paint influences the rusting of iron. What change occurs in the water levels in tubes P and Q?

May/June 2016

Which gas present in air is required for iron to rust?

May/June 2017

A steel bicycle that had been kept outside for several months was beginning to rust. Which action would not lower the rate at which corrosion occurs?

May/June 2018

A steel bicycle that had been kept outside for several months was beginning to rust. Which action would not lower the rate of corrosion?

May/June 2018

A steel bicycle that had been kept outside for several months was beginning to rust. Which of the following would not decrease the corrosion rate?

May/June 2018

A steel bicycle that had been left outdoors for several months was beginning to rust. What would not lower the rate of corrosion?

May/June 2018

A steel bicycle that had been kept outside for several months was beginning to rust. What would not lower the rate of corrosion?

May/June 2018

A steel bicycle that had been stored outside for several months was beginning to rust. Which change would not reduce the rate of corrosion?

May/June 2018

The diagram illustrates an experiment used to find out how paint influences the rusting of iron. What change occurs in the water level in tubes P and Q?

May/June 2019

The diagram illustrates an experiment used to investigate the effect of paint on the rusting of iron. How does the water level change in tubes P and Q?

May/June 2019

The diagram illustrates an experiment used to investigate how paint influences the rusting of iron. What happens to the water level in tubes P and Q?

May/June 2019

The diagram illustrates an experiment set up to investigate the effect of paint on the rusting of iron. What happens to the water level in tubes P and Q?

May/June 2019

The diagram shows an experiment designed to investigate how paint affects the rusting of iron. What occurs to the water level in tubes P and Q?

May/June 2019

The diagram illustrates an experiment used to investigate the effect of paint on the rusting of iron. What change occurs to the water level in tubes P and Q?

May/June 2019

Which substance is required for iron nails to rust?

May/June 2021

A strip of aluminium is placed in dilute hydrochloric acid. No reaction is seen at once. Which statement accounts for this observation?

May/June 2021

Which statement gives the reason galvanising stops iron from rusting?

May/June 2021

Iron undergoes rusting when it is left in air. Which two substances present in air make iron rust?

May/June 2022

Mild steel is galvanised so that corrosion of the iron is prevented. Which of these statements about galvanising are correct? 1. Galvanising prevents corrosion because the zinc makes an alloy. 2. If the coating is damaged, water and oxygen still do not corrode the iron. 3. Zinc is a sacrificial metal and corrodes instead of iron.

May/June 2022

Which process employs sacrificial protection to stop steel from rusting?

May/June 2022

A magnesium block is fastened to iron so that it does not rust. Which statement concerning this rust-prevention method is correct?

May/June 2022

Which substances present in air are required for iron to rust?

May/June 2023

When iron rusts, which compound is produced?

May/June 2023

Which of the following statements about rusting is correct?

May/June 2023

Which statement best explains why aluminium seems to be unreactive?

May/June 2023

Which compound is produced when iron rusts?

May/June 2023

Blocks of magnesium are fixed to the underside of a steel boat in order to stop rusting. Which equation represents a change that prevents the steel from rusting?

May/June 2023

Iron water taps are often electroplated with a chromium coating. Which statements give reasons why iron water taps are electroplated?

May/June 2024

Which of the following statements about the rusting of iron is correct?

May/June 2024

Iron undergoes rusting when oxygen and water are both present. Which statements concerning the rusting of iron are correct?

May/June 2024

Iron is a metal, and it has a high density together with a high melting point and a high boiling point.

May/June 2024

The diagram illustrates an experiment used to investigate the corrosion of iron. What change occurs to the water level in tubes P and Q?

May/June 2025

The diagram shows iron nails that are left for one week in separate test-tubes under the conditions illustrated. Which test-tubes provide evidence that rusting has occurred after one week?

May/June 2025

What is rust’s chemical name?

May/June 2025

Galvanising stops iron from rusting. Which of the following statements about galvanising are correct?

May/June 2025

Zinc is applied to iron by galvanising so that rusting is prevented. Which statements are correct?

May/June 2025

Submerged steel pipes may be guarded against corrosion by fixing magnesium blocks onto them. Which equation shows the reaction that stops corrosion?

Oct/Nov 2016

Steel boats can be safeguarded against rust by fixing blocks of a more reactive metal onto the boat’s hull. Which statement is correct?

Oct/Nov 2016

A metal, X, is used in the construction of oil pipelines. X rusts in air and water. X can be protected against corrosion by fastening blocks made of element Y. Which statement is correct?

Oct/Nov 2016

Iron is a metal that rusts when oxygen and water are present. Mild steel is used for .....1..... and its rusting is stopped by .....2..... . Stainless steel does not rust. It is made by .....3..... iron with another metal. Which words fill gaps 1, 2 and 3?

Oct/Nov 2017

Iron is a metal that rusts when oxygen and water are both present. Mild steel is used for .....1..... and is protected against rusting by .....2..... . Stainless steel does not rust. It is made by .....3..... iron with another metal. Which words fill gaps 1, 2 and 3?

Oct/Nov 2017

Iron is a metal which rusts when oxygen and water are both present. Mild steel is used for .....1..... and its rusting is stopped by .....2..... . Stainless steel does not rust. It is made by .....3..... iron with another metal. Which words go in gaps 1, 2 and 3?

Oct/Nov 2017

Four iron nails were each wrapped with a different metal. The nails were put into an open dish of water and left for one week. Which iron nail is unprotected from rusting?

Oct/Nov 2017

A setup is shown for an experiment that investigates the effect of galvanising iron. The setup is then left for seven days. What change occurs in the water level in tubes X and Y?

Oct/Nov 2017

A block of zinc is fixed to the hull of a steel boat. Steel is an alloy of iron. Which statement describes why the zinc stops the iron from rusting?

Oct/Nov 2017

Give one observation you would make during this reaction.

Oct/Nov 2017

The diagrams illustrate experiments on the rusting of iron. A student made the following prediction about the results.

Oct/Nov 2018

The diagrams illustrate experiments on the rusting of iron. A student made the following predictions. Which of these predictions are correct?

Oct/Nov 2018

The diagrams illustrate experiments on the rusting of iron. A student made the following prediction. Which of these predictions are correct?

Oct/Nov 2018

Aluminium articles do not require protection against corrosion. Iron articles do need protection against corrosion. What is the reason aluminium resists corrosion?

Oct/Nov 2018

The diagrams illustrate experiments on the rusting of iron. A student made the following predictions. Which of these predictions are correct?

Oct/Nov 2018

The diagrams illustrate experiments about the rusting of iron. A student made the following predictions. 1. The iron nails rust in tube P. 2. The iron nails do not rust in tube Q. 3. The iron nails do not rust in tube R. Which of these predictions are correct?

Oct/Nov 2018

The diagrams illustrate experiments about the rusting of iron. A student made these predictions. 1 In tube P, the iron nails rust. 2 In tube Q, the iron nails do not rust. 3 In tube R, the iron nails do not rust. Which of these predictions are correct?

Oct/Nov 2018

Iron rusts, whereas aluminium is not easily corroded. Which statement explains why aluminium resists corrosion?

Oct/Nov 2019

This question concerns metals and metal oxides.

Oct/Nov 2019

Rusting of iron can be prevented by fixing a piece of a metal that is more reactive, for example magnesium, onto the iron. Which equation shows the reaction that occurs?

Oct/Nov 2020

What causes aluminium metal to be unreactive in air?

Oct/Nov 2020

Group I metals are highly reactive. Transition elements are metals as well, but they are less reactive than Group I metals.

Oct/Nov 2020

Four separate test tubes, each with water and an iron nail, are left for two weeks. Which nail had the smallest amount of rusting?

Oct/Nov 2021

Aluminium objects do not require protection against corrosion. Iron objects must be protected against corrosion. Which statement accounts for aluminium's resistance to corrosion?

Oct/Nov 2021

Coating iron with zinc stops the iron from rusting, even if the zinc layer is scratched. Coating iron with tin also stops the iron from rusting, but if the tin is scratched the iron beneath begins to rust. Which statement is correct?

Oct/Nov 2021

Aluminium objects do not need protection from corrosion. Iron objects must be protected from corrosion. Which statement gives the reason that aluminium is resistant to corrosion?

Oct/Nov 2021

Which statements show why zinc is used to protect iron from rusting?

Oct/Nov 2021

Aluminium objects do not need any protection against corrosion. Iron objects must be protected against corrosion. Which statement explains why aluminium is resistant to corrosion?

Oct/Nov 2021

Ships are constructed from steel, which is an alloy of iron. Blocks of magnesium are fixed to the underside of ships so that rusting does not occur. Which statement describes how the magnesium prevents rusting?

Oct/Nov 2021

Which metal is used to galvanise steel?

Oct/Nov 2022

Three experiments, J, K and L, are arranged to examine rusting. In which of the experiments does rusting take place?

Oct/Nov 2022

Iron nails are kept in an airtight container. After a few days, the nails start to rust. How can rusting of the nails be prevented?

Oct/Nov 2023

Which gas present in air is required for iron to rust?

Oct/Nov 2023

The diagrams illustrate experiments used to investigate the rusting of iron nails. In which test-tubes will the nails rust?

Oct/Nov 2023

If a piece of aluminium foil is placed in dilute hydrochloric acid, no bubbles are observed. Which statement accounts for the absence of effervescence?

Oct/Nov 2023

Iron nails are kept inside an airtight container. After a few days, the nails start to rust. How can the rusting of the nails be prevented?

Oct/Nov 2023

Which gas present in the air is required for iron to rust?

Oct/Nov 2023

Which coating prevents iron from rusting even if the coating is damaged?

Oct/Nov 2023

The diagrams illustrate experiments used to investigate the rusting of iron nails. In which test-tubes do the nails rust?

Oct/Nov 2023

The diagram illustrates an experiment used to investigate the effect of paint on the rusting of iron. What changes occur to the water level in tubes S and T?

Oct/Nov 2024

Which word equation shows the rusting of iron?

Oct/Nov 2024

A section of a steel ship is prevented from rusting by using a sacrificial metal. Which metal would be suitable for this role?

Oct/Nov 2024

Which statements about the use of sacrificial protection to stop iron from rusting are correct?

Oct/Nov 2024

Several ways of stopping iron from rusting are given. 1 alloying with chromium. 2 greasing. 3 painting. Which of these are barrier methods?

Oct/Nov 2025

The following four methods can be used to stop iron rusting. 1 alloying 2 coating with plastic 3 greasing 4 painting. Which of these are barrier methods?

Oct/Nov 2025

Which row shows the methods used to stop iron from rusting?

Oct/Nov 2025

An iron nail is completely coated with zinc so that it does not rust. Which row names this protection method and explains why zinc is chosen to protect the iron nail?

Oct/Nov 2025

Fig. 1.1 displays part of the Periodic Table. The symbols shown are: H, He, Li, Na, Ca, Fe, Zn, Au, Al, C, N, O, S, Br, I, Ne. Use only the symbols of the elements in Fig. 1.1 to answer the questions below. A symbol may be used once, reused, or not used at all.

Oct/Nov 2025