Uses of Metals (Cambridge (CIE) O Level Chemistry): Theory Questions

Aluminium is used in the manufacture of aircraft because of its low density.

Explain why a low density is important for a metal used to build an aircraft.

The strength of the metal is also important when choosing a metal to build an aircraft.

Explain why strength is important as well as low density.

Aircraft bodies are made from an alloy of aluminium rather than from pure aluminium.

Suggest two reasons why an alloy is used.

The body of an aircraft is made from aluminium alloy, but the landing gear is made from steel.

Suggest why steel is used for the landing gear.

A company is designing a lightweight ladder that will be carried to building sites and left outdoors.

State two properties the metal used to make the ladder should have.

The company chooses aluminium rather than copper for the ladder.

Explain why aluminium is the better choice.

The ladder is left outdoors but does not need to be painted.

Explain why the aluminium ladder does not need to be painted.

Suggest one disadvantage of making the ladder from aluminium rather than from steel.

The frames of windows in modern buildings are often made from aluminium.

Suggest two properties of aluminium that make it suitable for window frames.

Window frames are not usually made from iron.

Explain why iron is unsuitable for making window frames.

Aluminium is a good conductor of electricity.

Suggest why this property is not a reason for using aluminium to make window frames.

Aluminium is used to make food containers as well as window frames.

Explain why the same property of aluminium is useful in both of these very different uses.

The table shows some properties of aluminium and copper.

Use the table to explain why the body of an aircraft is made from aluminium rather than from copper.

Use the table to explain why the electrical wiring inside a house is made from copper rather than from aluminium.

Suggest one property, not shown in the table, that would be important when choosing a metal to make a water pipe.

A manufacturer wants to choose one of these two metals for the base of a saucepan.

Explain why the table does not contain enough information to make this choice.

Magnesium has a lower density than aluminium.

Suggest why the bodies of aircraft are made from aluminium rather than from magnesium.

Titanium is a strong metal with a low density. It does not react with body fluids.

Replacement hip joints are made from titanium.

Suggest two reasons why titanium is suitable for this use.

Explain why a replacement hip joint is not made from iron.

Gold does not corrode inside the body.

Suggest why hip joints are not made from gold.

Aluminium is used to make food containers because it resists corrosion.

State one other large-scale use of aluminium.

Explain, in terms of its properties, why aluminium is suitable for that use.

State a property of aluminium that would not be a reason for the use you gave above.

A student says that aluminium is suitable for every use because it has a low density and it resists corrosion.

Explain why the student is wrong. Use one example in your answer.

Suggest why aluminium is not used to make the cutting edge of a knife.

Overhead electrical cables are made from aluminium.

The electrical wiring inside a building is made from copper.

Copper is a better conductor of electricity than aluminium.

Suggest why a different metal is chosen for each of these two situations.

An engineer suggests using a thicker aluminium wire inside buildings instead of copper, so that it carries the same current.

Suggest one disadvantage of doing this.

Silver conducts electricity better than copper.

Suggest why silver is not used for either overhead cables or household wiring.

State the property, other than conducting electricity, that a metal needs for both overhead cables and household wiring.

A student is asked why aluminium is used to make food containers.

The student answers that aluminium has a low density.

Explain why this is not the main reason for this use.

State the property that is the main reason.

The same student is asked why copper is used for electrical wiring.

The student answers that copper is malleable.

Explain why malleable is not the property needed here.

State the property that is needed.

The student is then asked why aluminium is used in the manufacture of aircraft.

The student answers that aluminium resists corrosion.

Resistance to corrosion is useful in an aircraft.

Explain why low density is nevertheless the more important reason for this use.

The table shows some properties of four metals.

Identify the metal that is most suitable for making overhead electrical cables.

Use the table to justify your answer.

Metal K is the best conductor of electricity in the table, but it is not suitable for overhead electrical cables.

Explain why.

Identify the metal that is most suitable for making food containers.

Explain your choice.

Explain why metal L would be unsuitable for electrical wiring, even though it resists corrosion.

Aluminium is used to make food containers because it resists corrosion.

Explain why resistance to corrosion is especially important for a metal that is in contact with food.

Food cans made from steel have to be coated on the inside.

Aluminium foil used to wrap food is not coated.

Explain why.

Aluminium is higher than iron in the reactivity series.

Despite this, aluminium objects left outdoors last far longer than iron objects.

Explain why.

Aluminium foil can be rolled extremely thin and still protect food.

Suggest two properties of aluminium that make this possible.